I was driving my son's EX and after 1 hour of driving I smelled a strong sulfer smell and thought it was a failing catalytic converter. I was wrong it happened 2 times. When it died the second time, I had it towed. Then replaced the alternator (with built in regulator) and installed a new battery. It would not start but it would crank. Next I checked fuses the next morning. I missed noticing that there was a 7 amp current draw from the battery. I started pulling fuses under the hood and found the RR defogger fuse under hood removed the current draw so I too the relay out that controls that and that fixed the parasitic current draw. I found a blown fuse on the SRS (20 AMP) as well. Not sure if they are related. I have been trying to diagnose the no spark condition. No spark from the coil. I removed the coil and got ~16k from + to output spring. From + to - it was very low as I expected. How can I test to see if the ICM (which was about 2 months old) to validate it is good? I could not get the probe on my test light (other end grounded) would not flash (or at least very notice able)

 

How can I check the ICM and the ECM signals? One of the two does not appear to be function. I also do not hear the fuel pump prime. I pulled the main relay and saw no sign of charring or cracked solder joints. Help me please! Ron I saw your advise on another thread that said to check fuses 44,31,13 - I had checked fuses Thursday and did not find an issue then again looking for the 7A parasitic draw. I suspect it is the ICM, I don't have the money to purchase both.

 

I just checked the fuses and #44 was blown and I replaced it. I heard the main relay click not sure if I heard the fuel pump run. Checked 44 fuse again and it had blown. Not sure where to go from here. Also I found 63 (20A) fuse blown and replaced it and it blew again immediately with no key turn. Fuse 31 and 13 were and are still good. Any suggestions for next steps?
I followed RonJ@HT thread and unplugged all injectors and the IACV (Pretty sure I got the correct part) Gray connector aimed down at about 8 O'clock has cylinder motor on it. When I did this 44 fuse still blew. I want to check the ECM/PCM but not sure how to identify connectors and I do not want to screw up. Wanted to validate A10 and A23 voltage to ground (From a tbleshoot Guide I found.) I looked for C116 and C130 but did not locate them.

 

I just located the "a" 32 pin connector and put a new fuse in and it stopped blowing the fuse. I believe from your other post Ron you said it would be the computer. oh Also I plugged in the IACV and all the injector connectors as well. Please confirm as I am not totally confident in what I am doing based on your other post.

https://honda-tech.com/forums/showth...A11+A24+ground

 

Your overcharging alternator unfortunately has caused a lot of electrical problems.

Is 15A hood fuse 44 still blowing? Does it only blow with the key in ON(II)?

Have you also checked whether dash fuse 9 is blown?

 

Yes it caused a great deal of poor luck. I was working it back to health and now it seems worse than ever.

15 A - is not blowing with computer unplugged (Connector A large 32 p on the left side)

I just checked the Dash #9 and it was fine. (That Said I never located C116 and C130. I may have spotted the brown one but it was taped and when the "A" connector unplugged it did not blow the fuse from under the hood.)

Replace computer, then is there anything else you recommend?

I just went to LKQ salvage looking for a computer but the only one I saw was in the same year but was an automatic. I was going to look on the internet. Are there specific sub codes I should look for because my computer has the numbers first line "37820-p2p-A34" next line is "921-346178" and company looked like IPT

 

Don't replace the ECU yet.

Do this:

1) Unplug ECU connector A.
2) Turn key to ON(II).
3) Ground terminal A16 in the unplugged ECU connector.
4) Does the fuel pump run as along as A16 is grounded or does fuse 44 blow?

 

I performed this and the fuse did not blow and the fuel pump did not run. I used a wire strand to go into connector on position 16 and then clipped it to the ECM mounting screw. I am lost but trust you completely. I found an ECM on EBay. looks like it will match what I need. Any next steps??? I assume either the Fuel Pump is bad or not getting power but the 44 fuse looks like it is short circuited inside the ECM correct?

 

Don't buy an ECU yet.

Unplug the main relay.

Turn key to ON(II).

In the unplugged main relay connector, use a piece of wire to jump voltage from the fuse 44 wire or the fuse 13 wire to the fuel pump wire.

Does the fuel pump run for both tests?

 

I took the main relay apart and there was no appearance of charring or bad solder joints. I did not however try to actuate the relay and measure that connection. While at salvage I picked up an extra main relay since I made the trip and they did not have the computer (ECM/PCM) I was hoping to find.

 

To do this where do I connect to the Fuse 44 (ie remove fuse and clip on to the live side of that fuse?) or am I trying to supply battery to the fuel pump wire which I assume is connected to the main relay.

Do I pickup the fuel pump wire from the main relay connector?

Sorry I feel like I should know this but I am very new to this level of testing.

 

Jump terminal 5 or 7 to terminal 4.

 

Thanks I will test it now.

 

Thanks Ron - That just verified that the fuel Pump is good. Now either the control circuit for the main relay is bad or the main relay is bad correct? Does this validate the ECN is Bad or short circuited some where?

 

Did both tests (5-4 and 7-4) make the pump run?

 

Sorry I thought it was either or. I shorted 7-4 I will check 5-4 next I have to work on helping another kid so after this one I am done for today. I will try to as soon as I can.

 

If the pump also runs with the 5-4 test, then clean and tighten the G101 ground wire connection on the thermostat housing. Afterwards, unplug ECU connector A, turn key to ON(II), and try the A16 ground test again to see if the pump runs. Make sure pin A16 that you are grounding has a Grn/Yel wire.

 

That connection is pretty tough to get to but I can do that what in your experience is the best method for cleaning? Wire brush?
I have left the ECN connector A unplugged the whole time.

I take it you suspect a poor ground connection. Why would the regulator event make that ground a poor connection. It was actually running well prior to the battery boil.

Thanks again for the help. I definitely need to get better at the troubleshooting.

 

This^

It's just one of the possible causes that must be considered, like doing the 5-4 test and redoing the A16 ground test.

Assuming the test was done correctly, the failure of the A16 grounding test to make the fuel pump run points to a problem unrelated to the ECU.

 

I will retest this on good Friday. I assume maybe I made a mistake I could not find the schematic on the web. I did find a service manual I will look at. I had to stop to Pay Taxes and work my 2ndjob - Umpiring. Friday Saturday Sunday I will be working on it again in the hope that the answer does come. Also another problem is the ABS fuse number 63 keeps blowing. (20A) in under hood box. Does that help? I ma not sure if I mentioned it before.

 

Nope. Separate issue.

 

I just retested the A16 grounded. It did not make the fuel pump activate that I could tell. I got the car in the air and found the connector under the intake manifold. I could not get the cover off I will work more on that one later. I had already ordered the new ECM and have a used one in hand. I did have the Main relay plugged in as well.
****New Information
The hazard light 10A fuse in under hood cover blew and there is a 20A I found blown that says door lock unit. I went and bought a probe that shows green and red for ground and power (Harbor freight logic probe) I am going to recheck all the fuses again with that to see if I missed anything else. With this I tested the engine ground and it was green or connected everywhere I attempted to check (Valve cover, with the probe connected to the battery and I validated the A16 wire was ground or green with the key on.

During the A16 grounding of the ECM connector with the connector unplugged I turned the key in 2nd position. The 20A fuse blew again. in the key off position the fuse does not blow.

 

Fuse 51 blew (20A) Power door lock control and fuse # 53 - 10A - I just found the numbers in a reference manual.

 

Connector A unplugged no fuse in 51 or 53. Radio works, all power windows work, headlights do not, Hazards signal do not, Turn signals fast click but both work from inside, Horn works, interior lights work, light for the rear defroster lit so I assume it works. heater fan motor works, still no fuel pump, power mirrors work, moon roof did not (I think that was the fuse I pulled though.)

 

Brake lights and reverse lights both work also. I am lost!! the starter motor still turns too. G551 and G552 appear to be related from a schematic I am trying to follow it is harness J and gets connected to the power door lock control unit power window main switch (which allows control of rear windows but not the front windows) Where do these grounds get made? Is it reliable to use the test probe to check if the ground are sufficient or should I start cleaning the grounds one by one?

I just cleaned Battery negative to body ground, Ground to the thermostat housing, and the frame to motor ground above the transmission.
They are all good. I also forgot I had pulled the window rely under dash and now the front window regulators are all functioning. Seems odd to me there are still no headlights. I still have not plugged in the A connector of the computer. Not sure if that is required to make it work. Verified G401 under dash with logic probe showed good ground back to battery.