Does anyone here knows what kind of signal I need to have from the ECM on the cooling fan relay pin for it to work ??
I have replaced the Relay (solid state module) when I ground the control pin on it, the fans work fine, but they dont work when I switch the AC on or when the engine is hot. I have checked the wiring and get a 1.8 ohm on the wire from the ECM, so I replaced it I get 0.3 ohms now which is a good contact I believe, but still it does not work.... All of this happened after I washed the engine....bad call.....
THANKS FOR ANY HELP !
gas28man
03-01-2006, 04:43 PM
I would look for the coolant temp sensor to see if it didn't take kindly to a soaking. Just a guess. This oughta throw a code, too. Have you had your trouble codes checked?
Rick
epselrice
03-01-2006, 04:48 PM
Yes, I have had the codes read, I got P1491.
The coolant temp sensor that you mention, would it affect the way it is reading the temp on the instrument panel ? Because it is reading fine.
Or is it a separatre sensor ? THANKS!
epselrice
03-03-2006, 08:58 AM
How many temperature sensors does the caravan have ? The temp gauge is working, does this men that the computer should know when to turn the fans on and off ? THANKS !
Chet42
03-03-2006, 05:06 PM
The fan is tied directly into the temp sensor (1 sensor), to test the sensor remove the plug from the temp sensor and the fan should run, its on top of the thermostat housing and has a 2 wire plug. If the fan doesn't run your fan "Relay"or the AC switch may be the problem. Also check the relay for proper ground. The relay is grounded by its case to the fender so ensure theres no corrosion between them. The temp gauge is on a seperate sensor its beside the temp sensor on the thermostat housing and has a (1 wire) plug.
The AC is also controlled by the same system, with a switch added to the AC control panel in the cab, once you turn on the AC the fan runs automatically, if it doesn't again check the sensor. Remove the sensor and dry the pins out and use electronic cleaner spray to get rid of any access moisture. If that don't work, replace it.
