ryaned380

'96 civic EX coupe. Adjusted my timing last night. Prior to that I grounded the little blue tach/service wire that's under the hood next the driver side shock tower. Ungrounded it when I was done. Tach hasn't moved from zero since. Used my meter to ohm out the wire and its not grounded still. Getting constant .022 V(insignificant) with car idling and at various rpm's. Turn signals, speed, fuel and temp gauge still working just fine. Could I have partially messed up the ECU?

canadaek

uumm why on earth did you ground that ??? odds are you fried your tach your suposted to jump the two pin wire in the passager kickpanel inside the car tach is driven off of the ignitor in the dizzy if your car still runs it's ok see if you can borrow a cluster to try.

ryaned380

I've check every fuse under the dash as well and they're all good.

ryaned380

I grounded it because I seen someone do that in the past when they were adjusting the timing on my car.

canadaek

well that's not the way you do it that is the tach test port for use when working on the engine not setting the timing.

Former User

^This or you fried the ICM inside the distributor.

ryaned380

oh damn. Well thanks for the info though. I'll start lookin for a cluster.

ryaned380

I think I've replaced that before. Would the car not run if I had fried the ICM.

Former User

I presume you can fry the tach part of the ICM without affecting the spark function.

canadaek

i am curious if this is possable. please let us know

ryaned380

I'll dig into this problem tonight or tomorrow and let you all know.

ryaned380

Checked a blue wire from my dizzy plug that a wiring diagram said was the RPM output and I'm still getting like no voltage so I bet the ICM's rpm part is fried. Since I had just replaced it four months ago, hopefully Checkers(O'reily) will replace it under the warranty.

ryaned380

Yep it was the ICM rpm output. Checkers gave me a new module for free and now I've got a working tach. Thanks guys for your input.

canadaek

well thats good next time if your not sure ask before you break something

ryaned380

I had a high school moment... I thought I knew everything until I realized what I didn't know. But yeah, next time I'll ask.

BTW where is the blue two-pin service plug that has been mentioned? Is it just under the dash below the glove box? If its behind the passenger kickpanel, then that looks like a pain in the *** to get to cause it looks like one big piece running the length of the door.

canadaek

just above the kickpanel should be in a bright green plastic holder but somebody could of left it hanging .. kick panel is 2 parts just have to lift up the door sill on the one end to get it off but you should be able to find it with out removing it.