Electric Fan Help

[jsett83]

I'm 99% certain the engine is reaching 210. The first fan kicks on and I continued to let the truck idle for an extended amount of time. I sent my harness out to have it cut down and it came back labeled with a green wire labeled main fan and a blue wire labeled aux fan. I believe the main fan relay is the one that is working. Not sure on what pins wires are coming from.

[Crash_OK]

Originally Posted by jsett83

I'm 99% certain the engine is reaching 210. The first fan kicks on and I continued to let the truck idle for an extended amount of time. I sent my harness out to have it cut down and it came back labeled with a green wire labeled main fan and a blue wire labeled aux fan. I believe the main fan relay is the one that is working. Not sure on what pins wires are coming from.

The second fan will not come on until the wire from the PCM goes to ground. My 5.3 has never got hot enough idling to kick in the high speed fan. It will if I have drove it for some time and then come to a stop.

[jsett83]

Interesting. My factory temp gauge does not seem to be too accurate,so was worried about not having both fans before driving. How long do you think I would have to drive to find out?

[Crash_OK]

Originally Posted by jsett83

Interesting. My factory temp gauge does not seem to be too accurate,so was worried about not having both fans before driving. How long do you think I would have to drive to find out?

I don't know... depends on a lot of variables. If you had a OBDII reader you most likely could get the water temp that the PCM is seeing. I have a scan gauge 2 that has that functionally.

[jsett83]

Good info, thanks! I will try to get my hands on a code reader.