Radiator fan always on while car running?

KODAFFYDUCK

MEMBER
2008 DODGE NITRO
3.7L
6 CYL
4WD
AUTOMATIC
86,000 MILES

Soon as you turn on the car the Radiator fan turns on and doesn't turn off until you shut off the car?

All fluids are fine, car doesn't overheat, seems like it gets up to normal operating temp on the gauge, no check lights or codes thrown.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Hi,

Always running indicates a short to power. This could simply a damaged fan relay. On this vehicle there are two. One is located on the passenger side engine compartment and mounted on the radiator support. The other is in the integrated power module under the hood also.

I attached the wiring schematic below as well as the relay locations. Remove one at a time and shake them to see if anything sounds loose. Also, here is a link that explains how to test a relay and its circuit:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Let me know what you find. Please also note there could be a short in a wire connector at the integrated power module. They are known to corrode, break, or simply stop working.

Let me know.

Joe

See pics below.

Images (Click to make bigger)