My car 99 legacy Brighton 2.2l

 

So I have been having an off and on overheating problems for some time now. I just now found what has been causing it!!!

 

One of the radiator fans (passenger side) has stopped spinning. This problem fits the symptoms perfectly to the T. Car overheats when stopped, but does not overheat on highway.

 

I thought for sure it was a faulty fan and was about to go out and buy a new one. Thankfully I had some sense to test this faulty fan. Since there are 2 fans on the radiator I swapped them. The supposed faulty fan worked just fine on the other side. And visa versa, the passenger side fan will not spin.

 

Is it as simple as bad wiring? Because if it was a faulty relay wouldn't both fans stop working?

 

Is this something a novice could fix? Or do I need to take it to the shop? I've never worked on wiring before. Grrrr

 

Thanks!

It's not that simple - generally only the drivers side fan runs when the car hits the ECU's threshold. If the temp continues to climb the ECU should turn on the second fan but it depends on the programming and that changed from year to year I've noticed........ So it could be that you have a partially clogged radiator and the clogged portion is where the running fan wants to pull air.... did you wait and see if the second fan turns on? OBD-II (95+) ECU's have seperate fan control leads for #1 (driver's side) and #2 fans..... there are two fan relays in the fuse panel under the hood. You can swap them and see if the #2 relay will run the #1 fan.

 

GD

It's not that simple - generally only the drivers side fan runs when the car hits the ECU's threshold. If the temp continues to climb the ECU should turn on the second fan but it depends on the programming and that changed from year to year I've noticed........ So it could be that you have a partially clogged radiator and the clogged portion is where the running fan wants to pull air.... did you wait and see if the second fan turns on? OBD-II (95+) ECU's have seperate fan control leads for #1 (driver's side) and #2 fans..... there are two fan relays in the fuse panel under the hood. You can swap them and see if the #2 relay will run the #1 fan.

 

GD

 

Wow this gets even more complex. Thanks very much for the reply BTW. I thought that when you turn on the air conditioning both fans turn on. This is how I tested it by turning on the AC. Although when it overheated today, I popped the hood and only 1 fan was running.

I'm looking at my fuses and there is a 20A main Fan, above that is a 10A unit back-up. Why would they be different amps should I still swap them to find out?

It turns out, the fuse for the main fan was blown. (I wish I had checked this first ....

 

I have a theory on how this happened. The car overheated from a headgasket leak, which pushed the water out of the resevoir. The connector for the fan is directly below this. This connector then got submerged in all the water coming out and blew out the fuse. It's interesting though that one of the fans will still run with a blown fuse.

It's not that simple - generally only the drivers side fan runs when the car hits the ECU's threshold. If the temp continues to climb the ECU should turn on the second fan but it depends on the programming and that changed from year to year I've noticed........ So it could be that you have a partially clogged radiator and the clogged portion is where the running fan wants to pull air.... did you wait and see if the second fan turns on? OBD-II (95+) ECU's have seperate fan control leads for #1 (driver's side) and #2 fans..... there are two fan relays in the fuse panel under the hood. You can swap them and see if the #2 relay will run the #1 fan.

 

GD

 

I am having an issue with the drivers side fan, the owners manual shows the fuse box under the dash board but doesnt tell me anything about the relays under the hood (90 leg 2.2). So are the two relays closest to the firewall in the relay/fuse box the fan relays?