mikem77

I just got my LQ4 fired up. I let it get up to 210 degrees and I still had no fans turning on. I double checked the wiring to my diagram and all the related fuses. I am not sure where to look next.

I have a PCM from Speartech with a primary fan and a secondary fan wire. The system grounds through wires running back to the PCM. I used the following wiring diagram to run the wiring on my relays.

Any help would be great.

S10Wildside

Checklist...
- PCM BLUE 42 (primary fan) to relay coil
- 12v ignition to other side of relay coil
- PCM RED 33 secondary fan) to relay coil
- 12v ignition to other side of relay coil
- PCM calibration setup for enabled fans and appropriate temps for ON/OFF

That's about it as far as turning on each relay.

fptransport

first.. when you say that the temp gets to 210, what are you using to get this reading? reason why I ask is because on my application my gauge was reading around the 250 degrees, but it was because the gauge was not reading the temp properly..
try applying ground to the relay to where the wire coming from the pcm connects to and it should turn on the fan, also check the wire coming of the pcm for ground? and also the relay needs a second +12v wire that is used as a ingition to complete the circuit inside the relay when the pcm sends the ground signal,, make sure that wire is "hot" when the car/truck is running