Quote:
Originally Posted by kglowacky
running a 2002 trans am LS1. Been driving for 2 years no issues. Cooling fans connected to the PCM Dark Green Wire and dark blue wire, these are both negative signal wires connected to 2 separate relays. Pretty sure set at 195 and 205. I decided to hook up my A/C factory retro and ran a totally separate fan wiring system with its own relays and triggers off the compressor power. When running A/C the fans come on always and temp sits at 190. BUT now when I don't run A/C the fans don't come on. I ran it up to 217 and no fans. I took a ground and touch the dark green wire between the relay and PCM and I get fan same with the dark blue wire. This tells me the problem is the pcm it is not working sending the negative signal at temp. Is this a sign the PCM is going bad. I assume my temp sensor is working as the Snap on scanning is getting a reading, Your thoughts??? I am going to check the wiring from the relay back to the PCM next.
|
So here is how my fans with A/C is wired using a trinary switch. I do not use the PCM as I have an PMW external controller. Regardless of that, the fans only kick on when the A/C pressure is above a certain PSI as detected by the trinary switch.