CCRM Problem

[joshwfl]

My ac and fan have always worked normally. A couple weeks ago my ac compressor quit, so it was replaced. I immediately had an overheating problem. The ac blows cold and the fan runs for about 5 min, then the fan will shut off and the ac cycles on and off. I have replaced the CCRM twice now with brand new RCM12M. Both still had the same problem.

I have tested the fan by running direct power, and both high and low speed work fine with direct power. When running the fan this way the ac never cuts off.

I hard wired the fan on high speed and put on over 120 miles today without a problem. Is it really possible that I bought 2 bad CCRM's, or could there be another problem? I know I could just put a toggle switch on the fan, but I don't want to ghetto rig my ride.

 

[COramprat]

I'd go back and look at the compressor install. Did you do it yourself or did someone else install? If a shop put it in take it back and tell them the issue you are having.

I don't think you would get two bad CCRM's. It's possible I guess but not likely since the fan probably would not run at all once the relay inside the module went bad. Do you have a volt meter? It would be easy to check the CCRM if you do.

If the car was running hot it would cause the AC to shut off or cycle intermittently.

 

[wmburns]

Check the low speed fan aux fuse. It is located in a smaller right hand side engine compartment fuse box. It would also be handy to know if the low speed fan ever kicks on (AC off).

Confirm if the high speed fan runs at all (AC on) at initial start-up. Also confirm if the fan turns on when the electrical connector to the engine temp sensor is disconnected.

Do you have an ODB2 scanner? Can you monitor the fan speed PID?

Some MY's use a thermal circuit breaker to protect some devices. The CB will automatically reset once they cool down. What may be happening is the fan is drawing too much power. After 5 minutes, the CB opens. With no fan, the engine will overheat AND the AC will cycle on/off due to over pressure.

Suggest looking at all ground points. Are they clean and tight? There are two smaller connectors under the battery junction box. Check to see that they are clean and tight. Check the connector to the fan itself. Is it in good repair? Any signs of over heating?

A function test of the CCRM can be done by grounding out the CCRM DB (pin 14) wire. This should cause the low-speed fan to run. Next ground the LG/VT (pin 17) wire and the High-speed fan should run. If this tests works, then the problem has to be in the wiring between the CCRM and the PCM.

 

[HISSIN50]

Good advice above. Were your pressures (notably the high-side) ok after the recharge?

You might want to check the trigger signal for the HEDF at the CCRM.

As WMBurns noted, some fan circuits have a CB. One some fans, it's on the pigtail connector where it plugs into the fan.

Good luck.