Rep Power: 0

2001 Civic EX 5 Speed - LOVE MY CAR!

I need a 37820-PLR-A03 replacement.

Car symptoms
With key in "on" position, relays clicking constantly, won't crank.
New Alternator
New ELD
All power and grounds checked

I can't think of anything else it could be other than ECU.

If anyone has one they want to part with, please let me know.

 
Rep Power: 518

Someone didn't get the alternator bolts tight enough, now it's burned out the PCM?

Fix the root cause or you will burn out every new PCM you install.





Any new PCM will need programmed to the immobilizer keys before the engine will run. That means a trip or tow to a dealer.

 
Rep Power: 0

If I pull apart the old PCM, do you think I can find evidence that it burned? I'm also confused as to how loose alternator bolts could burn a PCM.

 
Rep Power: 518

No.

It's the most common cause of PCM failure in this car. This PCM is damn near bulletproof------ until someone leaves the bolts loose after a timing belt job or alternator replacement.
Ton of posts and threads with symptoms including gauges acting weird, reduced power and limited RPM, check engine light on but can't communicate with a scanner, immobilizer light on.

It's so common there's even a service bulletin about this problem.


BUT WAIT
Hold on a minute, wait. This don't make sense:

What are the lights on the dash doing during this time?
When did this problem start?
What work has been done shortly before this started happening?

What have you done to check out the "won't crank" problem?? This is not related to the PCM at all.

 
Rep Power: 518

Do either of these look familiar?

 
Rep Power: 0

Tomorrow I'll plug the ECM back in and shoot a video.

The problem leading up to this, was the alternator not charging. I replaced ELD, then Alternator then Battery. The last time I drove it, I got home, and suspected the battery dead, and it was. So I charged it, and then out of EXTREME frustration, cycled the key on/off/on/off/on about 30 times, then the clicking started.

Service wise, I'd been driving it for over 5,000 miles since it was in the shop, and when I had it in the shop, I did struts, brakes, throw out bearing, clutch, lower control arms, timing belt, water pump.

 
Rep Power: 0

Yes, those look like the passenger side grounds. Both replaced new when we were working on it.

 
Rep Power: 518

The grounds in the picture are on top of the upper radiator hose neck.
The small wires are G101, the most important ground for the PCM.


Go back to the "won't crank" and start diagnosis there. The starter is a simple system, completely unrelated to the PCM.

Maybe if you figure out the "won't crank" problem the other stuff may clear up as a result.

 
Rep Power: 0

Remember, I drove the car home. The "wont crank" manifested after. I'll shoot some video of the dash, and the sounds the main relay is making.

 
Rep Power: 518

Is the battery nearly dead? Charge it up and retry?

 
Rep Power: 0

Charged fully, then re-tried, that's when the "clicking relay" and no-crank condition started.