CCRM (IRCM) Quirk

[sperold]

90 SHO - Lets say the car has been sitting on the road for the day, when I first hit the key, the cooling fan comes on.
When I move it into the driveway and shut if off, and then go back and turn the key on, the cooling fan no longer comes on.
This does not trouble me much, but has anyone else experienced this?
Everything else seems to work ok.
I am going to check my grounds (the one partially hidden by the battery, and I am having trouble finding the one on the drivers side at the front of the spring tower, but eventually I will find it) and clean them properly.

I don't want to change my CCRM if this is a fairly common quirk, so I am asking first.

 

[SHOdded]

Were the fans running before you parked the car on the road and shut off the engine?

 

[sperold]

No, after the first "key up" the fans do not come on again until directed by the temperature sensor.

 

[rubydist]

Cooling fans coming on with the key turned to on is a symptom of bad ground on the pcm. You could have a bad ground, or your pcm could be failing - it might only work right after the circuits have heated up some.

 

[sperold]

Thanks Rubydost and SHOdded for the replies.
I can find the important ground on the fender top behind the battery, but the associated ground on the drivers side is proving to be hard to find. The fender mounted solenoid has a lot of wires associated with it, but I don't seem to have a dedicated ground on the front surface of the spring tower. I will snoop around in the harness for a take-out in that area that is not doing anything now. But all other functions are OK so the ground thing is a mystery if only one thing is acting up.

It will be a week or so before I get back to it, but I will let you know if the ground shine-up corrects this issue.

 

[SHOdded]

I believe there should be a ground next to/behind the battery location for the PCM as well as the battery itself.

 

[sperold]

I was so sure this was a CCRM issue that I blanked out the information that it is the PCM that is the issue. I will have to find the information on grounding the PCM.
Can anyone tell me what PCM is the correct one for a 90?
Also, is the PCM referred to by any other name?

 

[SHOdded]

http://rcmautomotive.com/id32.html

B9B/B1 if non-CA emissions, B9C/C1/WOZ if CA emissions for the '90. LOS and X2J will also work with the '90 if non-CA

 

[sperold]

Is this thing also referred to as an EEC (Electronic Engine Control Module)?

 

[SHOdded]

Correct. EEC-IV in our case.

 

[luigisho]

Should be able to crawl around and look at your PCM with the glove box dropped down and see the code somewhere. My '90 was B9B1. Info posted above I believe is correct regarding replacement models.