VX V6 Ecotec fan control

[VX L67 Getrag]

Its been a while since I've looked into a ecotec overheating issue as it doesn't happen very often if all is looked after well!

I think it's correct but just checking low speed fan is passenger side by itself & hi speed is drivers side by itself?

Seems a little weird as I thought they may run them together & change voltage for hi speed, but looks like this car tests like that & both seem to work fine!

[vs ss]

Hi vx l67 getrag yes that is correct, small passenger one for low speed and drivers larger one for high speed.
On high they should both run together.

Edit! Just went and tested mine and this is correct

[VX L67 Getrag]

oh really well when I bridge my hi temp fan relay it only runs the driver's side, I wonder if sending the manual command will be different & run both relay's at once rather than just bridging relays separately.

Thanks for checking VS SS

[Dylan]

If it makes a difference. From memory the low speed is switched via the BCM and high speed from the PCM.

[VX L67 Getrag]

Yeah I was 99% sure of that too, so maybe the bcm keep low speed on while hi speed is on, but 99% sure from looking at calibration that low speed comes off as hi speed goes on!

[vs ss]

All I do to check the fans is start the engine and pull the coolant temp off.
Then you should get low then high a few seconds later and this is an easy way to test the whole fan circuit.
You are right as it does turn of low speed but this relay has two sets of contacts, so as the relay turns off low to go hi this lo speed relay sets up the low speed fan to then stay on by getting power through this contact from the high speed fan relay.This way they could keep it quite using the single fan on low(which most times is enough for a good cooling system)
but in turn can use both on hi without causing any feed back issues or the need for another relay.
It is hard for me to make sense on a keyboard,but hope you sorta get your head around it.
Cheers vs ss.

[VX L67 Getrag]

Yeah that makes sense, thanks again!!!! NICE IDEA!