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  1. #1

    Default Strange electrical behavior - need advice 1996 5.7 L

    Hello - just joined the forum so hopefully someone can help.* I have a 1996 Sea Ray 190 with a 5.7L Mercruiser (carb) with Thunderbolt V ignition.** It ran fine all last year, and when I last took it out in December (Sunny San Diego).* It sat under boat cover but suffered several very rainy days since last used.*Inside of boat was damp, but no reason to think I got watter in distributor*or anything like that.
    *
    On my checkout run a couple of weeks ago, about 20 minutes in I noticed my voltmeter was low - around 10.5V.* I revved the motor and the volts jumed to 14.5, so I settled it back to idel and the voltage stayed at 14.5 (at idle).* The motor would idle fine and the system would charge at ~14.5V, but when I then tried revving the motor, voltage would drop as speed increased, until eventually the motor sputtered and died. The only other thing I noted out of the ordinary was that the tach was reading ~300rpm with the motor and key off.* It seemed to read correctly at speed, but never returns to zero.*
    *
    Brought the boat*home, tested the batteries, and battery connections (all ok), and then yanked the alternator (having convinced myself it was a voltage regulator issue).* Needless to say, I have a nice new alternator, and the same old problem.* Pulled the 12V feed to the starter (which is where battery, alternator and starter connect) and cleaned and tightened (it was already clean and tight).
    *
    Tonight, I followed the Clymer manual's advice, and confirmed (1) grey lead on tach was not grounded, reading ~12v, and removing the grey tach lead from the coil did not return the gauge to zero, (2) both sides of the coil read roughly 12v (3) the alternator output (orange wire) reads the same as the active battery, and roughly ~0.5v more than the reading at the dash voltmeter, (3) reistance between the positive side of coil and high tension (output) is ~10,500 ohms (manual says should be 7500-8500).
    *
    So in a nutshell, the motor runs rough, sputters, and trying to rev it usually causes voltage to drop and the engine to die.* It will readily start each time, but won't run smoothly or rev, and the voltage meter registers changes in voltage each time.*
    *
    I'm planning to do the following, as my last ditch effort:* remove all leads to the tach, in case it was shorting out the coil just enough to drop the voltage as coil firings increased.* Only reason I suspect the coil/tach is because of the false reading.* Apart from that, I'm not sure what else to do.* The advice I've seen is "check every connection" which is a bit useless as advice since there are hundred of connections, and no way I can be sure I can even see all of them.
    *
    Anyone have similar experience, or suggestions?* Could a short in the knock sensor, electric choke, shift interrupt switch, slave solenoid, or IC module cause these types of problems?
    *
    Thanks in advance - Jurisd

  2. #2

    Default Re: Strange electrical behavior - need advice

    OK, so bad form to reply to my own post, but figured I would update the facts and maybe simplify the problem. I believe I've determined that the tach is not the problem. I ran the motor this morning, and even when warm, it would run smoothly (alt charging at 14+V) for about 1-2 minutes, and then motor would die. I kept trying it until I got the motor to run consistently at idle. It stumbles a bit when revving quickly, and I get backfire out of the carb occasionally, but assume that motor runs ok now. So, the single thing to chase down is that when I rev the motor, the voltage showing on the dash gauge and multimeter drops - the faster the motor, the lower the voltage. I think that is the reverse of what I expect, but keep in mind I've already replaced the alternator and load tested both batteries. Any ideas?
    Last edited by Jurisd; 03-19-2011 at 02:23 PM. Reason: typo

  3. #3
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    Default Re: Strange electrical behavior - need advice

    I kept trying it until I got the motor to run consistently at idle. It stumbles a bit when revving quickly, and I get backfire out of the carb occasionally,
    Ayuh,... That sounds like a fuel delivery issue,...

    It's goin' Lean....

    As for the Voltage,... I'd assume the Alternator has an Issue....
    Any Grease is Better,... Than No grease at All....

  4. #4
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    Default Re: Strange electrical behavior - need advice

    You know what your timing is doing ?

    This was a like alt, to the one you had example one wire and you bought a one wire.

    Run the motor off a external tank of gas after cleaning the filter in the fitting that enters the carb, and disconnect the water sep and use fresh clean gas.

    If you find out the timing and clean the filters and it still runs f---d up then i would first check the dist, Then after fixing that i would run it still f---d up rebuild the carb. run it all on the external tank, till you get it running right.

    Say you cant get it running right do a vacuum test, and maybe a compression test.

    You got that thunderbolt ign. believe me we have 50 questions about f---d up thunderbolt older boats.

    Usually after a week of working on it you order a hei or other dist. bypassing the whole mess, and just one wire in and one wire out and one wire to the tack.

    Get back to us.

  5. #5

    Default Re: Strange electrical behavior - need advice

    Thanks for the advice. I suspect that the rough running was old gas, although I had to return the boat to storage before I could run it off a separate tank. I sprayed carb clearner, and pulled the cap and confirmed there were no cracks. I also checked the ICM to confirm no water had gotten in there. But, toward the end of the day, the engine was running smoothly (like it used to) and would accelerate revs quickly and without blow-back or misfiring. So for the moment, I want to focus on the electrical question, and next time I can work on it I will dig into the fuel systems issues more.

    For now, I need to determine whether the following behavior is wrong: At idle, the dash voltmeter registers a charging condition (13V+). If I increase the motor revs (say, from ~700 to 2K) the dash voltmeter drops to around 12V. When returned to idle, voltage restores to charging 13V+. Is that normal?

    Steps taken so far: Alternator was replaced with an exact new replacement with exactly the same specs and hookups, and belt tension is correct. Tachomoter was disconnected and connected, with no change to condition. Batteries were load tested, and I checked for continuity and voltage drops across the battery switch and cable to starter. Voltage at alternator was confirmed to be within 0.2V of the battery that was live, and registered ~.5-.7V above the dash voltmeter, and the multimeter drops when the dash gauge drops. I ran the diagnostic test in the Clymer manual for a Thunderbolt V, with the only issues being the coil resistance registering at ~10,000 ohms instead of the 7,500-8,500 called for in the test guide. Also, I could not figure out how to test the ICM.

    So, given that the motor runs OK and the only signs of trouble are the dropping voltage on increasing engine speed, any thoughts? Could a bad coil cause this? Would switching to electronic ignition potentially be a solution (and how involved is that?). Thanks - JD

  6. #6
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    Default Re: Strange electrical behavior - need advice

    For now, I need to determine whether the following behavior is wrong: At idle, the dash voltmeter registers a charging condition (13V+). If I increase the motor revs (say, from ~700 to 2K) the dash voltmeter drops to around 12V. When returned to idle, voltage restores to charging 13V+. Is that normal?
    Nope,... It should be showing 13.6V whenever it's runnin'....
    Any Grease is Better,... Than No grease at All....

  7. #7
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    Default Re: Strange electrical behavior - need advice

    Tighten your belt on the altenator..................

  8. #8

    Default Re: Strange electrical behavior - need advice

    I appreciate the ongoing help. Belt on alternator is tight - I just replaced with new alternator, and tension is both the same as before, and right at what the instructions said.
    So two follow-on thoughts: either the coil is faulty, and is giving spark correctly but using considerably more power than it is supposed to, or I have a short that is not enough to interrupt the current flow, but is enough to drain off voltage. Anyone know if a coil has been known to do that? I checked the main battery cable running to the starter and cleaned that connection. But maybe next is to remove the battery switch, and run a line directly from the alternator output to the positive lead on the battery.

    Anyone have a solid troubleshooting procedure for the ICM? (no knock sensor on mine). Mu Clymer manual doesn't really address it clearly.

  9. #9
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    Default Re: Strange electrical behavior - need advice

    disconnect the neg cable and follow it to the main ground on the block remove and clean that connection. Most forget that it takes a good ground also to make a circuit.

    Now if i remember correctly there is also another ground dead center of the motor just behind the motor between the bell housing.

    I remember helping pull a motor and there was a worn thru ground wire on that one.

    I could be wrong and you don't have one there.

  10. #10
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    Default Re: Strange electrical behavior - need advice

    Your altenator ORANGE wire May be suspect here. I would definately look closely. The battery selector switch may also be suspect so inspect carefully.

    Also there is something you need to do before you continue to JUMP to conclusions.....

    Get a digital volt meter
    attach meter across battery connections, and as second test across the battery ground and the point at which the alt wire connects to your battery switch.
    start motor.
    rev to 1500-2000 rpms
    read meter and tell us what is says..........if different from dash volt meter then we can discuss the issues........

    If you suspect a short in the wire harnes under running conditions you can make your own remote starting rig to run the motor without the main wiring harness connected to the helm. If you feel this is the way to go and need more info let us know and we can post advice on how to do this.

  11. #11
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    Default Re: Strange electrical behavior - need advice

    Also the ICM affects timing and could cause a running issue as you describe, I do not feel it wouuld cause a voltage drop as you see or describe.

    The way to check the ICM is to attach a timimg light to motor and number 1 spark plug wire close to spark plug, check timing at idle, ~ 6-8 BTDC, apply throttle and confirm timing advances to at least 30 dergees BTDC by 3500 rpms. If it does not then the ICM may be suspect.

    Chief, the wire you may be refering to may have been the continuity wire......The ground wire is typically attached to one of the bolts (studs) on the bellhousing.

  12. #12
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    Default Re: Strange electrical behavior - need advice

    yes to the bell housing the rest are screws that hold tight the bell housing to the motor.

    After re-installing that middle of the motor wire with a good end that motor i was pulling ran perfect, still is cause i ran into the guy in shoprite and he said it running good offered to take me fishing.

    One other thing i should have posted, the main barrel plug should be pulled apart and the holes cleaned.

    Seems every few years i wind up cleaning every single connection on my ole girl.

    Just make sure you disconnect the battery.

  13. #13
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    Default Re: Strange electrical behavior - need advice

    Also I am confused about something? do you have a KNOCK SENSOR or NOT?

    Just reread your posts, Does your choke open all the way? If not then this could be a issue?

    Is there any chance you got water in your gas tank??

    Also measuring a coils resistance is only a reference, The only true way to test is on a coil testing machine which puts it under load and simulates rpms/load and you can see and hear the spark it creates thru the entire rpm range in which it will be used. Thousands of coils are replaced evry year because it is a easy part to replace.

    One other coil check is to run the motor in the complete dark, look at the coil, if you see arcs jumping all over the coil then that could be cracks in the housing...this would need to be replaced.
    Last edited by kghost; 03-24-2011 at 07:53 AM.

  14. #14

    Default Re: Strange electrical behavior - need advice

    Wow, lots of good advice. I don't have the boat stored at home so it may be a couple of days before I can implement. But, for kghost's questions well above, I have already been through the voltage testing on the batteries, etc. The batteries read 12.7v and 12.3v at rest, and there is no material voltage drop from the positive lead across the switch, using either the battery ground or the block. Likewise, when running at 1500 rpm, the alternator output (at orange wire connection) reads the same (at least to three significant digits). There is a ~.3-.5V drop between the "back" (being the positive post on the battery, battery switch or alternator output) and the + post on the dash gauge, and there is also an additional ~.3-.5v error in the dash gauge (meaning with the same input, the dahs gauge reads a half volt lower than the digital multimeter). But the key point is that both gauges react the same to an increase in engine speed - they both drop, by roughly the same increment.

    Other questions: Nope, I have a TB V, but only an ICM, no knock sensor. Yes, it is possible that I have bad gas/water in the gas, and that could be an issue that causes the rough running, but I don't think it would explain why the voltage drops when the motor speed increases, since the alternator is new, putting out a full 13-14v at idle and the belt is not slipping. Yes, my choke appeared to be working correctly, was open all the way when the engine was warm, and fiddling with the choke plate changed the engine speed/smoothness but did not affect the voltage issue.

    So, I think my best move is to follow the simplest advice - start checking every wire in the ignition system for bad insulation, arcing, and maybe checking continuity/resistance. I'll start with the power leads, but yes, cleaning the grounds as well is a good point. If that doesn't clear it up, then I'll focus on the coil, and then lastly the $500 ICM. Thanks all, and I'll let you know what I find...

  15. #15
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    Default Re: Strange electrical behavior - need advice

    I would suggest to also seperate your dash from the engine at the large connector in the main wiring harness.

    Speaking of which have you pulled it apart and looked at he pins and sockets???????

    Do you have a good schematic of what you are working on?


    See attached.



    Attachment 1944

  16. #16
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    OK, so what your problem seems to be if I am reading right is that the output voltage from the alternator drops as RPM increases even though you have good connections and good belt tension. Where exactly is the sense wire connected? I'd try connecting it directly to the POS post on the battery with a temporary jumper wire and see what happens. I suspect a bad connection.
    Practicing the ancient art of ren-ching

  17. #17
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    jursid

    If I had to find a single point of failure to explain the two different faults ( 1, voltage drop at gauge; 2, Ignition erratic), Id suggest the instrument / Ignition harness plug at the engine.
    Its the big black round thing on the starboard side exhaust elbow. split it from socket, look for corrosion. you can spread the pins a little to get better contact, be very careful, they are easy to break..... use some magic spray, work it in and out a few times....

    BTW, Its not uncommon for the tach to sit in odd positions when ignition is off.

    If you can get a wiring diagram, you can make up a temporary test rig to bypass the fwd instrument/ ignition switch harness. a switch, pushbutton for start, few bits of wire pushed into the socket at the stb ex elbow...........be careful

    cannot see how a faulty coil could pull the voltage down. even if it was shorted out, wirng would be melting before the voltage dropped.

    It all looks to me as one or a couple of dodgy connections to me....look at the harness plug. dont buy the ECM yet.

    please confirm one thing. you say both the merc dash voltmeter and the seperate volmeter drop, where exactly is the seperate voltmeter connected? battery? alt output? battery switch? I cant believe the actual battery voltage is dropping, so work your way away from it until you see the drop. goodluck . Mark.

  18. #18
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    cannot see how a faulty coil could pull the voltage down. even if it was shorted out, wirng would be melting before the voltage dropped.
    Ayuh,... Ditto that, 'n the igntion mudule,...

    They either work, or they don't...

    I still see 2 entirely different issues,...
    The lean condition, runability issue, 'n the low voltage issue...
    Any Grease is Better,... Than No grease at All....

  19. #19

    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    Good stuff, as always.
    Kghost: Yes, I had pulled the master connector apart, and thanks for the diagram - that is the one I've been using from the Clymer manual.
    O2, others: The voltage testing I did used a digital multimeter, with the negative lead connected via 5' of 10ga wire to the negative battery terminal, and the positive lead connecting at (i) each positive battery lead, (ii) the alternator output (orange wire connector), (iii) the starter positive post, and (iv) the sensor lead on the dash voltage gauge. The voltage did drop at the battery post, the same as at the alternator output. But electrically this makes sense, as there cannot be a material difference between the two, if you assume that the wire between them has good continuity and no appreciable resistance.

    So, glad to know it's probably a problem that will be solved by time (checking continuity and wiring insulation) rather than by expensive parts (although the latter would be easier...). I hope to get the boat home this weekend, and I'll let you know what I find.

    JD

  20. #20
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    The schematic is a mercury one out of there manual so it is the real thing,

    also one very important troubleshooting proceedure is to disconnect the big connector and use a remote starting set up to isolate the engine wiring from the dash/wiring harness from the connector to dash as a suspect ( dash has 12 volts DC 10 ga wire feeding a lot of stuff and it comes thru the connector/wiring harness).

    You seem pretty good with the electrical so to make a remote set up you need a momentarty toggle switch and a on/off toggle switch. run a 12 volt 10 -14 guage wire lead to one connection on each switch ( one wire to switch and jump it to the other switch) and a yellow wire 14 ga connected to the momentary switch for cranking over (connected to starter or slave solenoid yellow with red stripe {small guage wire}) and a purple 14 ga wire connected to the on/off switch and connected to the + of the coil. Use good alligator clips. NOTE: good thing to have if keys are lost!!!!

    Turn on the on/off switch, activate the momentary until motors fires and release the momentary and the motor will run. turn off the on/off switch and the engine will shut off.............simple as that.

    after doing all this re test the out puit voltages at idle and 2000 ish rpms to see if there is a change. If there is then the problem is in the dash or wiring harness to the dash. If not then it is at the engine wiring harness. The purple wire on the engine that goes to the choke, coil, ingition module and THE ALLTENATOR EXCITATION CONNECTION. The other connection at the altenator SENSING connection is the RED/Purple which is also a 12 volt supply going to the dash that is the high current supply to the slave solenoid, the large breaker with the red button and is tied to the starter at the same point as the orange wire.

    Remeber one thing at a time..........

    If you still have a lack of charging voltage at 2000 rpms this is where I would think you need to be looking.......

  21. #21
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    Quote Originally Posted by Jurisd View Post
    The voltage did drop at the battery post, the same as at the alternator output. But electrically this makes sense, as there cannot be a material difference between the two, if you assume that the wire between them has good continuity and no appreciable resistance.JD
    Yes there can be a difference, If you dont make assumptions. we are looking for a wiring problem, dont assume you dont have one. anyway, problem is alternator or associated external wiring.

    Ok, voltage at battery post is dropping, so it must only be dropping from charge voltage (~14 VDC), to battery voltage (~12.6 VDC). (assuming battery is good).

    So your alternator output is going up and down.

    Purple wire from ignition switch (ignition system supply wire and alternator exciter wire) dodgy somewhere. this would explain alt output changing and ignition erratic. when you notice the voltage drop, jump from purple at back of alt, to battery positive. Alt output voltage should go up to 14 plus. let us know.........

  22. #22

    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    Resurrecting this thread, since I just now got the boat home to fix it. The motor seems to run smoothly, so just focused on the electrical issue now.

    I have cleaned the main ground with its 5 connections, but I must say, so far none of the connections I've scrubbed have been in the least bit corroded - previous owner kept the thing immaculate.

    I did the purple wire troubleshooting. Motor started and dash gauge showed 10.5V. When I revved the motor from idle, it jumped to 13V+ and stayed charging at idle. The orange wire showed 14V, and shunting the purple wire to battery + yielded no big change (since they matched pretty closely anyway). Engine ran at smooth idle for 15 min with system charging - thought I was in the clear.

    Went back two hours later, restarted, and with the motor at idle the dash gauge showed 10.5V. Shunting the purple wire to battery + made no difference, and the orange wire stayed at 12V. BUT, here's the twist. When I revved the motor, the system went into charge mode and seemed to work fine (aside - I would wlecome if someone can explain the whole field current thing, since it appears at idle the field is not active and so the alternator does not generate charge, but once revved, then the system works fine, even then at idle). But, when I revved the motor once the system was in charging state, the dash voltmeter dropped to below 12V, but the orange wire voltage remained at 14.5V. So... is it possible that the dash voltmeter has a short somewhere, and is reading nearly correct at times, and then totally wrong others?

    By the way, I tried disconnecting the main plug and starting the motor by shunting from the yellow/red wire on the starter solenoid to the battery+ using a pushbutton remote starter from Harbor Freight. The starter turned, but there appeared to be no spark, as the engine would not fire. Is there some other connection that is needed to get power to the ignition system in order to start (again with the helm isolated from the engine)?

    Thanks - JD

  23. #23

    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    OK, further update, and partial resolution. I re-read Tuna's description, and figured out the remote start wiring. Hooked it up, disconnected the main buss to separate the dash from the motor, and put a digital meter on the orange wire ALT output. Started it up and wouldn't you know it, a straight 14.6V output voltage, that stayed constant at idle, fast idle, and even revving.

    SO. Looks like a problem in the front, which must either be a short or one or more bad gauges (starting with the OEM Sea Ray voltmeter. So, I'm off to the auto parts store for a new dash voltmeter (I assume there's nothing special about these that would necessitate getting one from Sea Ray?), and then I'll crawl underneath the dash and see if I can find an odd voltage drop between the tach and voltmeter (those two troublesome ones). Hopefully, I'm just hours away from the end of this...

  24. #24
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    The dash wiring,

    the volt meter gets its voltage signal off the purple wire in the guage/dash wiring harness.

    The volt signal is created or originates at the KEY switch. When the key is in the run position battery voltage is transfered from the B+ on the key switch to the purple wire. follow the purple wire to all connection points and see if there is a issue.

    focus on the key switch. Infact rerun your test and do a digital voltage meter test between a ground point (black) wire on the dash and the purple wire at the key switch. see if the same voltage seen at the orange wire is there also and under the same test proceedure(idle, 2000 rpms, etc etc.) If it is then check it where it connects to the volt meter in your dash. If the voltage is the same as the orange wire then it has to be the dash guage!

    Also look closely at the wiring behind the dash, there may be a ground buss with many grounds attached. Mkae sure they are good , there may also be one for battery + even a fuse panel so look and observe closely to see if any connections are weak or oxidized!!

    keep us up to date when finished.........

  25. #25

    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    Thanks KGhost. I think you may be on the right track in suspecting the key switch - here's why. I reran the test this afternoon, confirming again that with the engine isolated from the dash (using rmote start), increases in RPMs had no effect on the orange or purple outputs from the ALT. With the dash connected, the bad behavior showed consistently - output on the ALT dropped with increasing RPMs.

    So I first cleaned the ground bus, and checked each of the wires. Two of the four (including the heaviest) showed continuity with resistance at 1 ohm or less (could be the run of test wire or the 18g test leads). Two others showed open circuit (which makes sense since they derine their ground from being connected to the buss).

    Then I isolated the dash voltmeter and reran the test, with the same results - dropping ALT output with increasing RPMs when the dash is connected, and no drop when the dash is diconnected (I redo this just to make sure nothing changed).

    So not I will remove the key switch and replace with the remote start rig, and see if that resolves the issue. Then I will return the brand new voltage gauge I purchased this morning, since that wasn't the culprit (doh!)

    If anyone has further suggestions based on the above, let me know. Otherwise I'll update in several hours on the switch test.

  26. #26
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    Some key switches can be serviced/taken apart and the contacts cleaned. Mine is such a key switch. Small tangs that can be carefully bent back and the switch may come apart......Key switches or the connections on them can cause a lot of issues......

  27. #27

    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    Well, it sounded promising, but I've removed the switch and used the remote start rig in its place - same problem. Suspecting the tach (since it all of a sudden is reading 700 rpm with the ignition off), I removed all three purple connections from the tach and then connected just two (hot and the one that was required to start engine), and tried it again. Still same problem, the voltage drops when the motor's RPMs increase. I've already fully disconnected the stereo, so the only other thing I can do is start one-by-one disconnecting the gauges. Any thoughts on which to focus on first?

  28. #28
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    listen two cheifalen i did and got rid of thunderbolt v dist, and put n a delco remey good choice took 15 mins to install!!! and 40hrs to figure out what was wrong,chief said do it i did!!! good choice these guys know what they are talkn about they know there s$$t!!!!

  29. #29

    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    Mikey - are you suggesting that my distributor is the issue, or is this unrelated to the voltage issue?

  30. #30
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    Default Re: Strange electrical behavior - need advice 1996 5.7 L

    OK I think we need to take a small step back

    Can you determine which PIN in the large wire harness connector is the Battery voltage that goes to the dash/key switch? PIN 6 on the connector (red/purple)

    If so disconnect the connector, Hook up your remote starter rig to the motor, do your voltage check at the connector pin. One meter lead to the pin, one to ground. Does your voltage equal the test of your alt, orange wire??? If so we can say the engine wire harness is good. If not the we have an issue with the motor wire harness/connection within the harness. If it is good then go to next step....
    Next:
    If you removed the key switch from the picture and hooked up your remote rig then once you started the motor did you check the charging voltage on the BATTERY + going to your rig? This should show the correct/same charging voltage as the orange wire at the motor. (same connection). YES OR NO voltage good or bad?

    If you have the correct charging voltage on the battery+ at the key switch then trace the purple wire that comes from the wire harness.......Once you find this, where does it terminate??? Is it the Key switch location? Ok if it does terminate at the key switch remove the purple wire from the key switch!! do NOT connect any other wires to the purple connection/wire from the harness. Re do voltage test, WHat is the result?
    This removes all ignition on/purple wire connections and components at the dash area......

    (The schematic says that the purple wire connects to the key switch, then goes thru the lanyard switch then back to the tachometer and then to all other guages)

    If you have propper voltage with only battery + and purple from the wire harness then you have a issue with the guage cluster or connections there.

    If you do not have the correct voltage at the battery + to your rig or the purple wire comming from the wire harness the it may be a harness issue.

    Try this and post back please.......
    Last edited by kghost; 05-02-2011 at 07:53 AM.

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