I have a 96 Accord V6(220K mi) with a problem with the AC compressor. The compressor stopped running a little while ago and a mechanic identified the problem as an ECM ground issue. To prove his point, I witnessed the compressor working when the ECM/ac compressor connection was grounded to the vehicle however the ECM alone will not ground the compressor. I've tried 2 addtional used ECMs to no avail. Is this truely an ECM issue or is there some other problem that I should be looking at. p.s. I don't want to purchase a NEW ECM from the dealer($$$$) and find that this is not the problem. Please help!!

Thx!!!

 

id check the wiring coming from the ecm. Make shure you dont have a break somewhere. What happens if you just leave it manually grounded. Will it always try to run then?

 

I am leaning toward the harness as well, I just could not believe that three different ECMs had the same problem. Unfortunatly if a manually ground the compressor it will run until it burns up. Thanks, I'll focus on the harness wires coming from the ECM.

 

STOP!!!! Before you burn something up. Its not a wiring harness or an ECM problem. The ECM does not supplie a ground on its owen, it recieve a ground and the interprits it, then sends it out. I will put money on it that he never checked the ground/ signal going into the computer. More then likely its going to be a faulty therma-con switch in the evap box. You will need to suck down the a/c system and remove the evap box and measure the resistance in that sensor. Easy to find its the only one thats clipped to the fines of the evap core. Its either going to be 1 or 2 wire sensor. This is more then likely your problem.

 

Turbowa,

Thanks for your suggestion, this is the only one which pointed to the evaporator unit. Coincidently, the evaporator function was my first concern when I purchased the car over the winter. You see the AC was then working but it was so cold that the vent was spitting out snow flakes!!! At that point I checked the feon levels and decided to see what happened when it really got hot, unfortunaly the ac compressor stopped working before I could test it over a longer period of time. BTW, Where is the therma-con switch in the Honda parts diagram? Also, should I replace the evap altogether?




Modified by 96AccordMD at 10:39 AM 6/26/2008

 

Item #19 is the part your after. But on your car as old as it is I would prob. just replace the whole unit.

http://www.hondaautomotivepart...+UNIT

 

sounds like the thermosal in the evaperator theres 3 wires plug on it with a wire going into the evaperator what you can do to test is jumper the in and out wires (not the blk/yel power) but double check the colors first before trying.

 

how would one measure the resistance? My car is having the exact same problem.

OP did you fix your problem?

I followed the manual for checking the thermostat and it works just fine, but how would I check resistance?

Here is my original post: https://honda-tech.com/zerothread/2341535

 

All,

Thanks for you help, I replaced the AC thermostat using the instruction from a previous post here, without taking out the evaporator. The A/C unit runs fine now!!