I've ran into a wall here. The relays are both good, and i've borrowed a good pcm. My haynes manual doesn't have a diagram for the cooling fan system. All I can see is that a dark blue wire runs from the pcm to the 2/3 relay. Is there one wire for each relay, 2 and 3, that runs to the pcm, or just one for both relays?

 

bad fan clutch (internal short)?have you checked for voltage and ground after the fan?

 

Not yet. The low speed still works fine, check anyway?? It probably doesn't matter, but when I try to manually command them on with hptuners I dont hear a click at the relays like I do for the low speeds..obviously. If I had a diagram and could see where all the damn wires run from the 2/3 relays it would help, versus having to pull **** apart and trace wires.

 

is this for your truck? or the z??

if one of the speeds works thenground should be good, because i believe they have a common ground.

 

Its for my car. Im running the 2001 harness and fuse box under the hood also..

 

I checked continuity on the blue 2/3 relay wire from the plug by the pcm to both on the fuse block, nothing. Guess I have a break somewhere in the signal wire. Simple enough fix..

 

I have this diagran for the LS1 F-Body. It is for the dual Fan low/high speed.
Hope it helps:

 

The dark blue wire was broke right after they splice together from the relays. Thanks anyway