Fan sensor

[Jerald Cate]

Can someone tell me what sensor turns these fans on?  I've never seen them running even with the engine at operating temperature.  I've tried to follow the wires but it gets lost in a big wire bundle headed towards the front right side of the engine.  The fans work because I've disconnect the connectors and applied 12vdc and they both turn on.  Also, I'm assuming these exhaust heat from the engine compartment?

Bruce Cate

[Dick Simonis]

I've been wondering the same thing.  Must be a way to test them and find out if they are even working.

[Gerald Farris]

Bruce,
The fans on your engine access door are probably not OEM, so I can not say how they are powered. However, if they are OEM, they are powered by a timer probably located in the LF electrical bay that is designed to turn on the fans at start-up and run them for 30 minutes after shut-down to prevent heat soak in the bedroom from the engine.

Gerald

[Michael Rump]

Hi Bruce,

My fans were controlled by a snap disc thermostat located on the drivers side wall in the engine compartment (about level with the top of the engine).  I moved the wires to the curb side rear door near the batteries and installed a switch since the thermostat was not working.

Hope this helps!

[Jerald Cate]

Dick,
My unit has a couple of spade lugs about 6 inches off the fan assembly, I disconnected the spade lugs and connected a 12vdc source to make sure the fans were working.  If as Gerald says mine are not OEM equipment yours may not be wired the same.

Gerald and Mike,
Thanks for the input that gives me a couple of places to look.  I like the timer idea, if I can't find a timer or thermostat I might install one.

Bruce

[Dick Simonis]

I thought the fans were OEM since so many seem to have them.  I'll nose around for a thermostat and see what I can find.