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popsbluejazz
Nov 24, 2007, 05:58 PM
Thanks to all of you sharing their experience and especially to the expert advisers. I have a 92 Accord that died on the road one wet night (yes it rains here in Oregon). Someone said replace the fuel filter, and so I did (it was overdue anyway). Now I tested the spark plug wires and there is no spark. After reading some of the posts, I realized I should do the K test, and have the CEL light stay on after the 3 seconds. I also have been checking the voltage at the igniter, and have none. I also have no voltage at the yellow lead to the coil. The coil is shot, as the ohms are at infinity across 2 sets of terminals. I know I'm rambling, but can anyone suggest how to track an open circuit from the ingition coil to the ingnition switch?
It seems I have more information than the ability to process it properly.

TxGreaseMonkey
Nov 24, 2007, 06:14 PM
Since the CEL stays on, the problem is with fuses, ECM, main relay, or ignition switch. Therefore, check all under-dash and under-hood fuses with a test light or multimeter. Here's how:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-3.html#post252145

Next, clean the 3-P main ECM ground on the thermostat housing, apply dielectric compound, and perform the K-Test on the ECM. There's a real possibility the ECM is shot. The main relay and ignition switch are not as problematic as fuses and ECM.

After you solve the problem at hand, the link below may help you "weatherize" your Accord for wet weather:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-5.html#post520809

popsbluejazz
Nov 24, 2007, 08:05 PM
I'm going to try the K test and see how it works. A direction is better than no direction.

popsbluejazz
Nov 25, 2007, 04:28 PM
Thanks to The Lone Star TXGreasemonkey for leading me along the path to fix.
I did the K test on the ECM, and it had good voltage (about 5 v). That's between the MAP sensor (red/white) and the black probe grounded 1on the thermostat housing. Is that right? I saw the 3 P connector, but didn't know which lead to connect to if I was supposed to connect there.
I also jumped the diagnostic connector, and got an DTC 15 for ignition output signal. I also checked the fuse boxes, and the starter signal circuit (fuse #9) is dead (no voltage); this is in the under dash fuse box. Under the hood, my R and L headlight fuse circuits are also dead. The fuses are fine as I checkec them for continuity.
Does that help or confuse more? It seems there must be a connection between the ignition failure (DTC 15), the starter signal circuit failure (fuse 9), and the lack of voltage to the coil and ICM. Or have I been in the rain too long?
Thanks again for your help so far; it goes so much further than the manual (Haynes).
PopsBlueJazz

TxGreaseMonkey
Nov 25, 2007, 04:49 PM
DTC 15 = Bad Ignition Control Module (ICM)

AutoZone can test the ICM for free, but my advice is to replace them every 120,000 miles or 10 years, whichever comes first. This is definitely part of your problem. Here's how to replace the ICM and coil (which I'd recommend you do, while you have the distributor open):

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-4.html#post265896

Be sure to clean the main ECM ground. After replacing the ICM, let me know if the CEL goes out after 2 seconds.

Duane in Japan
Nov 25, 2007, 05:17 PM
Your starter fuse and headlight fuse more than likely only get power when those items are energized. Some things on your car are power side controlled and some things on your car are ground side controlled.

Power does not go through these fuses until you put the key to the start position or until you actually turn the headlights on, use your voltmeter to test, not the ohmmeter while power is applied to the fuses.

popsbluejazz
Nov 25, 2007, 09:34 PM
Thanks Duane in Japan for the reminder; much obliged.
Thanks again to TXGreasemonkey for the further direction.
My concern right now is that I have no voltage to the coil. I am pretty sure the coil is gone since the resistance is too high. But if I just replace the coil and ICM, what prevents the previous problem from recurring? Also, if I just replace the coil and ICM they most likely won't work due to lack of power still. Am I missing something here?
Confused in Oregon.:confused:

Duane in Japan
Nov 26, 2007, 10:18 AM
Extremely high (secondary ignition system) resistance can take out a coil. For years folks have put a screwdriver in the end of the plug wire and tried to jump a spark from the side of the screwdriver to ground, maybe trying to jump a spark across a half inch gap, this could take out the coil on many cars, GM HEI comes to mind. It is a good thing that you want to replace them as a set, the coil and ICM that is, that is a good plan in my book, expensive but safer.

You have no power on the black / yellow wire going to the distributor, this wire goes to both the coil and ignitor but you knew that. Do a continuity test on the black / yellow wire going back to the ignition switch. Jumper (back probe) battery power to the black / yellow wire at the distributor connector and see if it starts.

Just remembered, did you disconnect the distributor connector and then test for power on the black / yellow terminal on the car side of the harness of course in case of a short inside the dizzy.

popsbluejazz
Nov 26, 2007, 12:10 PM
I found out that my CEL light stays on if I leave the coil connector unplugged (probably a DUH for most of you folks). When I plug the connector back in, the CEL light goes out. I did try checking the voltage to the ICM unit inside the distributor after reconnecting both the connector and secondary coil lead to the coil, and it was still no volts. I will start to try finding the proper wire to check for continuity in the black/yellow, which becomes yellow after the coil. What it is when it gets to the ignition switch I'm not sure, but I'll check the wiring diagram, even though I don't trust Haynes very much. Especially after the Diagnostic code differences Txgreasemonkey turned me onto. Thanks to you Duane for all your assistance.

Duane in Japan
Nov 26, 2007, 07:11 PM
It should be blk/yel at the ignition switch, Honda uses this color for power on several systems coming off the fuse boxes or ignition switch.

Off memory, there are four terminals on the ICM, three of them are side by side, the middle terminal is the power input, is this correct.

Did you try jumping power to the distributor connector blk/yel? Use a sewing needle to backprobe the pin. Don't puncture the wire insulation.

popsbluejazz
Nov 27, 2007, 04:58 PM
You are right on, Duane. There are 3 terminals side by side and one on the end of the igniter. The middle one is the black/yellow and it has voltage now that I remembered to plug the coil back in before checking for voltage. Here's what I have checked on the igniter so far, and the results (with ignition switch on):
1. 12 V between the yellow/black (wire to the middle terminal) and ground.
2. 12 V between the light green (wire to the terminal toward the front of the car) and ground.
My Haynes manual says to check for continuity between the light green and the ECU. Also to check the resistance between the blue wire from the tachometer terminal and the igniter, but it doesn't say where on the igniter to check for resistance (of 1.1K to 3.3K Ohms).
To make everything just perfect, it says "If all the checks are OK, replace the igniter." This makes no sense to me, as if the checks are OK, the igniter would be OK.
Still confused in Oregon, but learning more with your great help.

Duane in Japan
Nov 28, 2007, 06:48 PM
Earlier you stated no power to coil, here you say you have power to the ignitor, Can you please verify your current situation, pardon the pun.

AutoZone can test your coil and ignitor, you also have not mentioned trying to jump power to the distributor connector (if needed, sounds like its not needed) blk/yel wire...

IF you go to AutoZone, can you explain how they test these items, I have not been back to the world in several years and they did not do this test before, thanks.

popsbluejazz
Nov 29, 2007, 11:28 AM
Thanks for the follow up Duane. I must have had some connectors unplugged or something, when I checked for power before. I redid my tests, and I have power to the coil, and to the igniter. Autozone tested the coil and it is OK. They just check the resistance across certain terminals and if it's in spec. it is good to go. It is looking more and more like the igniter, as TXGreasemonkey suggested earlier. I have been trying to get the igniter out, but the screws seem frozen, and I'm afraid I'm going to strip them out. I have half a mind to get some vice grips on them and turn them out. Do you have suggestions on how to get them out? All the checks on the igniter have been fine, except for the continuity test with the blue wire going to the tachometer terminal, since I don't know where that is yet. But I'm not sure what difference it makes, since the manual says if the checks are OK, replace the igniter!?
Thanks again Duane for your inputs.

Duane in Japan
Nov 29, 2007, 09:31 PM
I do not trust the resistance test on the coil, I guess AutoZone needs the ignitor too, I thought they put one or both of the items on a test machine, they must need both.

I use a pair of dykes to get stuck screws out, vise grips also work. I put the dykes perpendicular to the rounded (button head) screw, squeeze so hard that the dykes cut into the head of the screw making two indentations 180 degrees apart from each other, this bite into the screw head gives a grip on the head, then while squeezing hard and turning CCW, the screw usually comes out. Vise grips tend to do more damage, but as a last resort, I will use them too.

If you get it out, do not mix up the screws for the ignitor and the coil, the coil screws are shorter, putting longer screws in will pull the metal insert out and break the wire connection inside (unviewable), BTDT.

popsbluejazz
Nov 30, 2007, 02:38 PM
Duane in Japan,
Thanks for continuing to lead me along the proper path. I'll try the pair of dykes as you suggest first instead of the vice grips. I'll keep those screws separate too; thanks for the great guidance.

popsbluejazz
Dec 29, 2007, 04:48 PM
I wanted to close this question and thanks to Duane in Japan and TXgreasemonkey for the guidance; it was awesome, and led me to finally replace the entire distributor for 150 from Autozone. My mechanic cousin in FL says the distributor is a weak link for the Hondas, so you may want to try that first.