This morning when I got to work I noticed that my fans were on when I shut my truck off and they were on for about 10 mins. When I come out of my office to drive to another building it started really weak so what would cause this to happen. I checked all of the wire connections and they are fine so I'm thinking relay. I just disconnected the harness till I get home and figure this out. Saying thanks in advance

 

im thinking relay also......heck mine havnt even came on yet

 

Ya mine usually only come on when the ac is on but this sucks cause there on when the trucks off. I'm just gonna have to test each relay when I get home today. Does anyone know how much the relays are?

 

The trigger could be faulty(shorted or at threshold when it shouldn't be). This is the control side of the relay. Pins 85 and 86 on the relay. The trigger could be the HOT or GND side depending on how it is designed. You have to find out if the trigger is present when it should NOT be(Key OFF). It could also be the LOAD side shorted(Pin 30 which is 12Vdc shorted to N.C. contact 87). This would put power on the fans all the time(assuming that pin 30 is HOT when the key is OFF). Your fans would run constantly. If you find that the trigger is not the problem you can swap the relay with another one of the same type to see if the problem moves or disappears. Most of the time the fans fail OFF not ON like yours dues to pitted connector contacts from the high current the fans need to operate.

 

The connectors all look good I just did the e fan swap but I can't really check anything out cause I'm at work right now. I will check the pins on the pcm when I get home and also grab another relay and switch each one and test them.

 

kinda sounds like you cooked a relay... Have they been working fine up until now?

 

Yes they have been working great coming on at the temp they are set at. Just today I noticed them on and when I started my truck it was really weak so as of now there unplugged

 

I guess I'm just gonna have to go to an autoparts and have them cross reference the relay number and go from there. I have a blackbear 2 pin harness so does anyone know which relay would be the problem?

 

relays are cheap. just be sure to get the correct amperage rating. any auto parts store will have them. i have a few extras if you need them.

-patrick

 

Cool thanks pat ill hit you up later tonight If I can't find any but the auto parts store I used to work at is pretty legit