Atriticuss

I have a 2002 honda civic ex coupe. skipping the long story i rebuild the engine, replace the throttle body(used), crank position sensor(used), vtech valve/solenoid(used). Then I payed to have the transmission rebuilt after crapping out 2 weeks after engine rebuild. The car still didnt run right and shifted hard and still had codes for throttle position sensor, vtech, crank p.s. and electronic load detector so i took it back and he said it was electrical problems. the cel never did work i had assumed it was a burnt light bulb or it was disabled. He says maybe the ELD is bad so he replaces the under-hood fusebox with one from the junk yard with no luck then replaces the under dash fusebox with a new one, still no luck. Finally we buy a used ecm reprogram it and that didnt work so he tells me it has to be a short in the wiring somewhere and couldnt help me. i finally figured out if i unplug the TPS the car will run longer without going into limp mode and the hard shifting goes away but still shifts at higher than normal rpm and idles around 1200. suspecting a cut wire for the cel i change the bulbs in the instrument cluster and it still wouldnt come on. I looked at the most obvious wires but i cant find any obviously damaged or cut wiring. i also replaced the battery ground cable and im at a loss on what to do next. I do have a multimeter but i dont know where to start or what cable leads where or what voltages to be looking for. Oh yeah one last bit of info i didnt think relevant but it also has a code for O2 sensor but it's unplugged and the cat is replaced with straight pipe.

ezone

Mechanic is broken. Replace mechanic.


I would get a wiring diagram.
Find which wire at the PCM is going to control the CEL.
Then use a jumper wire to manually control the light from the PCM connector.

Then decide my next step based on the results of that check.

Atriticuss

Ok, i jumped green/orange wire from ecu E plug to green/orange instrument cluster b or blue plug wire and started the car and the cel light still did not come on. In fact the only lights that came on as i cycled the key and checked the connections on the jumper were the battery, oil, maint req, abs, P and brake.

ezone

Sounds like you only made a jumper to bypass the dashboard wiring. That's not what I meant.

Ground E31 (grn/org) by backprobing it at the PCM connector and see if that turns on the check engine light.

Now consider which pin position the same grn/org wire is in at the gauge cluster. Is it in position B3 or is it in position B21?
(years 2001-2002 grn/org should be B21, 2003-2005 LX-EX should be B3)


Is your cluster from the correct year and trim level car?
Has someone modified cluster wiring to use a newer cluster in it?

Atriticuss

ok i think im understanding this right, now. so i put the red probe in in E31 and grounded the black probe and got 0 volts. did the same on B21 green/orange and got 0 volts. Then i probed E24 yellow, which i think is the right one to send the signal and got 6.5 volts. while doing this i accidently pushed the turn signal and noticed it isnt working now either when it worked fine last time i drove it. i played with that a while, started the car which is actually idling at 1600 rpm now, played with it some more and i notice everytime i engage the turn signal the red light around P dims but still no indicator arrow however it still clicks and the bulb blinks.

ezone

........no..... I never said to use a voltmeter.


A jumper wire.




PLUS a paper clip







Connect one end of the jumper wire to a ground (usually the steel dashboard framework because it is chassis ground), stick the bent paper clip in the other jaw, and stab it into the back of E31 at the PCM. (See "How To Backprobe: http://www.enduringautomotive.com/how-to-back-probe-a-sensor/)

This will supply a ground to the CEL circuit, it SHOULD make the CEL light up when you turn the key on.


Do you have a wrong cluster for the car?

Atriticuss

i actually tried the jumper cable i made too which i soldered the ends to make it stiff and it still didnt light up when i grounded e31 but to be sure ill try a paper clip thats sounds like a better idea.

Atriticuss

ok, i tried the paper clip, it stuck in there real well and grounded it in different places and still no cel. each time cycling the key with no luck.

ezone

Continuity check between E31 and the cluster connector?


Notes from post #4


Now consider which pin position the same grn/org wire is in at the gauge cluster. Is it in position B3 or is it in position B21?
(years 2001-2002 grn/org should be B21, 2003-2005 LX-EX should be B3)


Is your cluster from the correct year and trim level car?
Has someone modified cluster wiring to use a newer cluster in it?

Atriticuss

i see no evidence of a cluster change, no adapters just wire harness and plug a and b blue and green to cluster i can take a picture and post it if you'd like.using a harbor freight cen-tech multi-meter i got 9.1 on the 200 scale for continuity between the 2 green/orange wires from the cluster to the ecu/pcm

ezone

At cluster connector B, which cavity is that grn/org wire in?

Atriticuss

Sorry, it's b21

Atriticuss

Atriticuss

the green orange wire is the second from the right on the bottom

ezone

Um, that's a data line for communication between the PCM and MICU. Boy, I hope you didn't hurt anything there...... that circuit is included in the transmission range (PRNDL) indicator schematic .

I suppose you've tried grounding that terminal directly to try to make the CEL turn on?




Any other weird issues with the cluster?
I've heard of people cutting a circuit to the CEL LED so it can't light up. (Fixing the problem is too hard, so lets create even more problems)


Do you have any friends with a 01-02 car you can try your cluster in, to see if it works? (diagnostic swaptronics)

Atriticuss

I did ground that pin and nothing. I thought I mentioned it but I guess I missed it. The only lights that turn on when I turn the key on is battery, oil, abs, maintenance req, P (park) and brake. Now when I started it brake stayed on and cruise control came on. I started it like 5 times since and cruise control no longer comes on. While running I cycled the gears all position light came on except for drive. I don't have a friend with a 7th gen civic. I spose I could get one from pick n pull $27 if you really think it would be worth it.

ezone

If you want a working CEL?

Seems like trying another unit is a good next step, one way or another.

Atriticuss

I'm still going on my mechanics words that the cars performance problems are do to a short somewhere and that's why I'm trying to tackle this cel/cluster issue as it seemed the most obvious place to start after replacing the main grounds on the engine. Could a bad cluster have effect on the engine and transmission?

ezone

IMO no. You can unplug the cluster and leave it in your recliner in front of the TV, it won't affect how the car runs and drives.

I wouldn't. See post #2.
FWIW your first post read as though your mechanics' diagnostic skills are limited to guessing at parts to replace.
Once he figures out he can't replace the problem away, he tells you BS so you and the car go away.

Each individual fault code should have been relatively straightforward to diagnose if one has the proper tools and service information.