1998 Dodge Caravan Engine Cooling Fans Not Working

ALYDAR66

MEMBER
1998 DODGE CARAVAN
6 CYL
FWD
AUTOMATIC
102,000 MILES

Hi, I have a 1998 Caravan and the engine cooling fans wont go on. Ive replaced the relay and the temp sensor. I have checked the temp sensor with a ohm meter to make sure the resistance changes when the engine warms up, and it does. Th sensor is working fine. When I pull the connector off the temp sensor the fans go on so I know the fans and fuses are fine. For some reason it seems the computer module isnt sending a signal to the relay to turn the fan on. I get the trouble codes P1491(radiator fan relay circuit fault) and P0118(engine coolant temp circuit high input). I am also having a problem with the air conditioning not working. When I do the self diagnostic test on the A/C the results are that it fails the cool-down test.

Does you have any ideas why the computer module isnt sending a signal to the relay? Could the A/C problem be causing the cooling fans not to come on? Could there be a problem with the computer module?

3 Replies

MASTERTECHTIM

MECHANIC
4,749 POSTS

The 1491 is usually caused by a bad fan relay and or a blown fuse feed to the relay. If ok possible bad computer

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Thursday, March 21st, 2019 AT 6:45 PM

ALYDAR66

MEMBER
2 POSTS

Im not getting the 1491 code anymore that went away when I replaced the relay. But I still get code P0118(engine coolant temp circuit high input) and the fans still dont go on. The sensor seems to be working because I tested it in a pot off boiling water and measured the resistance while it was still on the car. For some reason the PMC wont tell the fans to go on.