Posted: May 03 2011 at 5:52pm | IP Logged

So I've been reading a lot on here about the thermal control issues nissans have and am wondering if this could be the problem with my truck.  Registered here because of this issue.

2000 nissan frontier.

A/c compressor does not engage or click.  Blower fan works, a/c switch lights up when turned on.  No cold air at any time. 

Aux cooling fan doesn't turn on at any point that I've been able to tell. 

Tried switching the relays (same p/n) in the fuse box, no effect.  Got a brand new relay and tried in both slots, no effect.

A mechanic friend who is too far away to look at the truck has said there might be a switch/sending unit where the top coolant hose goes into the engine (there are 2... a one wire and a 2 wire) and if this was faulty it would make sense that it would knock out both the aux cooling fan and a/c compressor.

any advice on where to look/what to test?  The dealership of course just wants to replace the freon and compressor before looking at anythiung else.