Hello everybody, good day.

Straight to the issue... Equinox 05, overheating.

With engine running, and hot (very) the engine cooling fan is off, only ac fan on, on high speed. (Ac it's turned off).

With engine off (key in ignition), bypassing the low speed fan relay does nothing; bypassing the high speed fan relay, only turns on the ac fan. (Motor itself it's working, I connect it directly to the battery)(no blown fuses, the big ones)

I've read that there are 3 control relays, I'm only seeing the ones on the fuse block, where's the other, and what does it do!?

Am I doing the correct tests!?
Any insights on what may be wrong!?

Thanks!

 

Before doing anything else inspect the plugs going to both radiator fans.

IIRC there is a series/parallel relay that is hidden. The fans run in series for low speed and parallel for high speed.

The relays rarely fail, but the connection at the radiator fan motor plugs gets weak over time which creates heat and melts/ burns the plug. Eventually this snowballs to the point where one or both of the fans can't run because the connection isn't good enough to carry current. The plugs fail quite often, so rule that out before doing anything else.

Most of the time the plugs look fine until you look at the terminals and see the white plastic around them start to turn black/charred.

The OEM part number for the new plug is 88988506. Both fans use the same plug.

 

Thank you for your quick response!

I keep investigating on the internet and indeed found out that the fan connectors are a common failure point, I checked them and they both were fine.

So, finally found the location of the third relay, beneath the front facia, on the lower right corner (driver side), only relay there, you can't miss it.

All dirty and all, as expected for the location, pry it open... And voilá! One of the terminals was loose, most likely over heated because of that, and melted the plastic connector, luckily not to the point of deformation, so I re tightened the terminal and plug it back in! Fans on! Yey!!!

Now I can move again, definitely need to buy that relay connector, might anyone casually know the part number or something!?

So, not the fan connectors, but then again another melted connector issue on the cooling fans circuits, as common on this SUVs.





Anyway, thank you!

 

Glad to hear you got this fixed. Thank you for posting back with your solution. It may help others having the same problem.

 

I forgot to mention that the current OEM part number for that relay connector is 15306045. It is a common connector that GM has used in many applications since 1993.

 

So if I look at this relay and one of the plug in area are burnt or plastic melted replace the relay?