BF 130 Main Relay???

Help! Need some advice from a Honda smartperson. I have a 2003 BF130A3LA. Ran great until I spent 90 minutes removingmarine growth from it with a scrubby. Tilted it down and it started right up and ran for 30 seconds andquit. Squirted ether into the intake andit started immediately, i.e., ignition OK. Hit ignition switch and no sound from the HP fuel pump. Hot wired 12v to pump and could hear pump runand engine would start just fine. Pulledconnection at pump and found no 12v to the pump with the ignition on. Wacked the main relay with a screwdriverhandle and the pump came on. Enginestarted and ran for 15 seconds and quit. Wacked again and again got pump and engine run for 15 seconds. Replaced the main relay. Again, cranks, but no start. Hotwired HP fuel pump and it starts andruns. I’ve got 12V coming into the mainrelay, but nothing on the blue/yellow coming out. When the key is twisted to run position I get2 beeps and both lights go out. What am Imissing? Did I get a bum main relay? Maybe it just didn't want to be clean.

It is possible that you got a bad relay...but not very likely.

I would check your connectors for corrosion. Also check for any corrosion in the fuses/blocks. Depending on what you used to clean the engine....it could have caused corrosion on various contacts

Also, the fuel pump relay operates from two different places. It gets its +12v from the main relay through a resistor and diode and a ground from the ECU to operate for the 2 seconds before start up. When starting, it gets a solid +12v from the starter relay and the ground from the ECU.

Also check on the continuity of the light green/red lead to the ECU. That is where the ground originates.

But first....check connections. Maybe bang on the connectors with the screw driver. That might be the easiest test.....although probably not the best.

Another thing that might help narrow things down. Disconnect the lead from the starter solinoid from the starter. Since the fuel pump relay is supposed to run when you activate the starter, once you pull the single bayonet connector off of the starter, turn the key switch to starter and see if the fuel pump runs. If it does, then you just have to focus on the circuit that operates the fuel pump as the engine is running.

Mike

Mike, I have a 2003 BF115hp - similiar problem- it was running fine turned it off- the next day would not crank. HP fuel pump is not running for 2 seconds. Everything else seems normal no alarms etc..I think it is the Main relay-

I disconnected the pump and I only have 11v on the blue and yellow wire.
I checked all the connections starting at the FI 30 amp fuse and working my way to the HP fuel pump. I have 12v going into the relay but only 11v going out of the Main relay on the blue and yellow wire.

So I am thinking the contacts are going bad inside the Main relay.

I also noticed when I turn the motor over the11v drops to .7v - this check was done at the pump connector.

Before I order a Main relay, am I missing something?

Thanks Hutch05

It seems like you are in the right area. If you say that the engine will start and run if you power the fuel pump directly, how did you get it to crank?

Make sure you have a good 12v constant voltage at the white/red....going into the main relay.

Mike

It seems like you are in the right area. If you say that the engine will start and run if you power the fuel pump directly, how did you get it to crank?

Make sure you have a good 12v constant voltage at the white/red....going into the main relay.


Thanks Mike for getting back to me...I connected the fuel pump directly to the battery the pump started running, I cranked the motor using the key like you normally would. I get the double beep when you turn on the key like it always did. Just would not start until I directly connected the pump.

I did verify that 12v was at the red/white going into the Main relay and 11v coming out on the blue/yellow wire. I checked this right at the relay. ( I had to use jumpers )

I tried to find a loose connection and checked grounds. I have enough experience to know trouble shooting electronics can be tricky.

Have you seen the relays go bad on the Honda's?

Hutch

Yes.....

Mike - I replaced the Main relay did not fix it. Note they sent me the relay that ends with 014 which is not one of three in the parts manual) I saw on another thread where you thought it would work and it was a hybrid of the other 3.

Here is what I see - NEW MAIN RELAY 12v going in 0 voltage out to the HP fuel pump. Old Main Relay I see 12 volts going in and 11volts going to the HP fuel pump.. I have checked every plug connection, I'm beginning to wonder if it's the ECM..To refresh your memory if I unplug the HP fuel pump and hook it straight to battery the HP fuel pump runs and the motor will start (pump runs continuously). The moment I disconnect HP fuel pump from the battery the motor dies.

Here is something I never mentioned- when you turn the key on I get two beeps (normal) the green and red lPs come on but both go out in 1 second that doesn't seem normal.
Thanks,

OK....easy thing first. The red and green light should come on for a second or two and then go off. If you had the PGM and the Charge lights....the PGM light will do the same, but the charge light will stay on. Evidently, you do not have the pgm and charge lights.

The part # for the main relay has change three times.

38580-ZW5-004
38580-ZW5-014
06380-ZW5-303
06380-ZW5-000

There were issues with the 303, so stay away from that one.

It is possible that you have a bad new main relay. Here are the steps to test it from the manual....

1) Remove the main relay.2) Connect the battery positive (+)terminal to the main relay black/yellow terminal and the battery negative (-) terminal to the main relay black terminal. There should be continuity between the white/yellow terminal and the yellow/black terminal.3) Connect the battery positive (+) terminal to the main relay white terminal and the battery negative (-)terminal to the main relay light green/red terminal. There should be continuity between the white/black terminal and the blue/yellow terminal. 4) Connect the battery positive (+)terminal to the main relay yellow/black terminal and the battery negative (-) terminal to the main relay light green/red terminal. There should be continuity between the white/black terminal and the blue/yellow terminal.5) If there is no continuity, replace the main relay.

Do not connect the battery for longer than 30 seconds. Wait for at least 1 minute before starting another check.

One (not in the book) way to check to see if the ECU is sending the ground to the main relay.....with everything connected, back probe the light green/red lead going to the main relay. Connect one lead of your meter to the backprobe on the green/red lead and the other lead of the meter to positive 12v on the motor (such as the big lug on the starter.) Turn the keyswitch to "on" and watch for a 2 second 12v reading.

If you do not get it, check the continuity from your backprobe to the pins on the connector at the ECU. There should be two. Disconnect the connector from the ECU when you do the continuity test so you do not harm the ECU.

If no ground; the continuity of the lead to the ECU is good; and you tested the main relay, the most likely culprit is the ECU.

Mike
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