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2004 BF 225 Check engine light on but no alarm

Wasque

Contributing Member
First time poster, but I’ve been reading tons of posts going back years primarily covering thermostat issues and related cooling questions such as what’s the best product to use when flushing these engines - vinegar, salt away, salt off, salt terminator (Honda recommended) or others.

Today’s issue has to do with codes. I recently had an overheating issue where the engine would drop down to limp mode and I’d get a 20 second alarm but no light. I’ve since cleaned up the thermostats and discovered a hole in the housing which was actually blocked by mineral build-up. I plugged it with JB Weld’s SteelStik product and we’re back in business (I’ll change the t-stays this winter but just cleaned them up for now). HOWEVER when I had the alarm blaring, I wasn’t getting any red lights (the green stayed on), so that got me investigating the red lights. Well I cut the green and connected it to the oil level/overheat light to see if it would light up with the ignition turned to ON then go off once the engine was started, and it did. So as a result I decided to order 4 new indicator lights. I installed them yesterday and they all light up at the ON position and the green stayed on with the engine having been turned on as it should. The problem now is that the MIL check engine light is staying on!

Is there any chance that would be because I crossed the wires when connecting? That harness is 2 black wires and the replacement light has red/black. I temporarily connected the light to the harness and once the light went on, I stayed with that setup of the wires then used butt connectors to properly connect them.

Could it be that a code was thrown with the overheating and it just needs to be reset? If so, I’ll follow the shunt procedure to check and clear codes before taking it to a dealer.

I don’t have any issues operating the engine across the entire RPM range and I’m not getting any audible alarms either when starting or while underway.

I have the PGM-FI ignition with 4 lights.

Thank you reading this far and I look forward to thoughts.

-Chris
 
Update - I tried clearing the codes with the shunt, and got the 2 beeps indicating it was cleared, but the light was still on...Also tried swapping the light connection to the harness but that just resulted in the light not working at all.

any help would be great!
 
I disconnected that small 3 prong and the light went off...it was clean, then I reconnected it, and light remains on.

What else would you like to know that would be helpful, short of rewriting my original post!

bottom line is that the red light under the check engine light remains on, despite attempting to clear the code. There’s no audible alarm and the light only flashed when I was pressing the kill switch while trying to clear the codes.

thanks!
 
Does you charge light stay on? This is a little confusing, is this with engine running or not? And one more thing, when you say the check engine light stays on, is your DTC shunt still connected or not, because if it is your check eng light will stay on?
 
No, the battery charge light goes off once I start the engine. I definitely removed the shunt after I tried clearing the code before starting the engine.

The check engine light is staying on while the engine is running.- at the same time, the overheat/oil level light and battery lights are turning off, while the green oil pump light is staying on (good thing!).
 
Go to the 26 pin connector on the engine and find the pin with the red/blue wire going to it - it's pin #11. Pull the connector apart and check the pins for corrosion, bent, or otherwise messed up. Then measure the voltage on that pin coming from the ECU. Manual says with MIL on, 0 volts. With MIL off, 12 volts. Page 5-10. If that checks out, then you likely have a problem in the wiring harness to the console.
 
Thank you chawk_man, I'll see if I can do that test. So to clarify, the voltage should be 0 and if it is, than there's likely an issue somewhere else.

Should I have the key turned to ON or leave OFF? Also, should I touch the black on my voltmeter to the pin 1, Logic Ground 1?

Appreciate the assistance.
 
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With key switch off, hook up the positive probe of your voltmeter to that pin #11 coming from the ECU. Hook negative probe to engine ground. Have someone turn on the key switch while you watch the meter. Meter should initially read zero at the two beeps, then jump to 12 volts - at least that's what the manual says. If that is what you see, then the ECU is OK and you have a break or disconnect in your wiring harness between the 26 pin connector and the 3-prong connector going to your key switch.

(Note that this sounds backwards to me - one would suspect that the 12 volts would turn on the MIL light. But either way, turning on the key switch while your volt meter is hooked up should give you two readings - 0 volts and 12 volts.)

BTW - one other thing to check - make sure that the #11 pin is not pushed in. It should be the same height as all the other pins. Also, make sure that the female mate to that pin is not broken or corroded.
 
What do you think about the fact that the light went off when I disconnected the harness behind the ignition previously? Not sure what that does or doesn't mean necessarily...
 
I assume you mean the 3 pin plug, disconnecting that will make the battery and check eng lights go off because that is the harness for them.
 
Ive been following this thread the conclusion i come to is that there is a relay somewhere that does not open and close as it should when the mill light should go off after
+/- 2sec between logic pin 1 [negative] and pin no 11
 
PG1&2 go through the main PGM FI Main Relay and inside that relay there are 3 relays. Another question we must ask our self's does the buzzer work ,because if the mill light comes on it should sound the buzzer.
 
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I am not going to get in an argument here other than to say yes, there are three relays, starter, fuel pump and ECM. Ecm remains live once ignition switch is turned on, ecm cycles fuel pump via fuel pump relay for 3 sec, warning lights are energised for three seconds, again by ecm to show they are operating. Alarm is signaled by ecm. Check engine light constantly on indicates a wiring harness fault. Suggest you start your fault finding as described by Bill. This should tell you whether the problem is in the engine harness or the boat harness ( more likely)
 
PG1&2 go through the main PGM FI Main Relay and inside that relay there are 3 relays. Another question we must ask our self's does the buzzer work ,because if the mill light comes on it should sound the buzzer.

the buzzer does work...MIL light stays on but no blinking and no alarm.
 
I tried to locate the 26 pin harness to do the test but couldn’t find it...can somebody take a photo of theirs and show me? I was probably staring at it, but nothing looked like what’s in the shop manual! Thanks guys for all the help so far. Oh, I also tried resetting the check engine light again, and though I got the two beeps, the MIL light remains on with no alarm sounding.
 
Regarding the 3 pin plug, is there a way to test it to see if there's a break in that line somewhere, in a similar manner to testing pin 11 for voltage?
 
Yes, test it the same way - the prong with the red/blue wire going to it. It should be you the same results you get at pin 11 if the harness wire is good.
 
ok great, thank you...so hopefully those both check out - then I guess we'd go down the list of other potential issues.
 
Took my boat to a local Honda dealer and they determined 99% it was the ignition harness so I gave them the go ahead to order and install the new harness. Hoping that takes care of this issue. Thanks for the help - learned alot!
 
OK. That's what we suspected. Let us know how it works out. And if you don't mind, let us know what it cost you to have a shop replace the harness.
 
Yeah, I wasn't surprised, but certainly happy to not have him tell me there's a bigger problem with the ECM! He told me appx $100 for the harness and an hour of labor. This is being done at the same time as the impeller and vertical shaft bushing job.

Side note - he did say I have some corrosion at the bushing - to which I'm not surprised. My understanding is the newer designs have holes in that location. Has anybody drilled holes in their older models to do the same thing? Would seem to make sense but I'd love to hear from others with that experience. I am planning on repairing it with epoxy this week when I get the boat back. I have some JB Weld on hand. Any thoughts on an alternative and better product to use? I'll clean it all up with the dremel first, regardless of material used to patch things up.
 
Several years ago Aristakat posted a bunch of info on the same issue. I think he concluded that it was not practical to do it. Search this forum for his posts.
 
Several years ago Aristakat posted a bunch of info on the same issue. I think he concluded that it was not practical to do it. Search this forum for his posts.

Thanks chawk, I’ll search Aristakat’s posts...To clarify - wasn’t practical to fix the corrosion or wasn’t practical to drill holes?
 
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