LMTV radiator fan stuck

[Ronmar]

24v at the solenoid = fan OFF. No voltage at the solenoid = fan ON.. so when you unplug the sensor the power at the solenoid should disappear, which wpuld be perfectly normal.

It is also normal for the solenoid to energize when you turn on the ign switch and to de-energize and vent air every time you turn off the ign switch.

Does your solenoid even go "click"?

You could hook up a test light or a relay to the solenoid wires to insure the circuit is capable of delivering enough current to energize the solenoid...

 

[derpschitz]

24v at the solenoid = fan OFF. No voltage at the solenoid = fan ON.. so when you unplug the sensor the power at the solenoid should disappear, which wpuld be perfectly normal.

It is also normal for the solenoid to energize when you turn on the ign switch and to de-energize and vent air every time you turn off the ign switch.

Does your solenoid even go "click"?

You could hook up a test light or a relay to the solenoid wires to insure the circuit is capable of delivering enough current to energize the solenoid...

I've got a pretty good multimeter, there is definitely adequate power to the solenoid.

 

[Ronmar]

I've got a pretty good multimeter, there is definitely adequate power to the solenoid.

One of the first rules of electrical troubleshooting, besides not letting the magic smoke out, is that voltage is only good if measured good under load. The tiniest fragment of a crappy connection will still pass full voltage throughout the circuit untill current starts to flow when it is actually called upon to do some work...

 

[derpschitz]

Got it all solved. Dead solenoid was the cause. Got Colt's new one put in, works like a charm. Thanks everyone for the advice!