Cool Fan 1 issue
 

I have a 2008 SS/TC, with a ZZP tune. Currently I have noticed increased coolant temperatures upwards of 229f. I opened to hood only to see cool fan 2 (passenger side)working, cool fan 1 was not. To my knowledge at at temp as high as 229f both fans should definitely be on. Here are the steps I have taken to troubleshoot cool fan 1 not working:

1. Checked fuse, not blown, tried another 30A fuse anyways
2. Checked relay, verified it worked after applying resistance, tried another relay
3. Applied 12 volts to the fan, it turned on.
4. Checked cap on coolant tank
5. Reset ECU
6. Turned AC on and off to see if anything changed

Im out of ideas, does anyone else know what I should try?

find someone with hp tuners or a decent scan tool and use it to command the cooling fan on. this tests the entire fan system, if the fan works doing that zzp screwed up something in the tune.

That's a good idea to try. However, there is voltage going to the relay so the ECU is telling it the car to turn that fan on. But maybe the tune overrides that idk.

i believe the ecm switches the ground circuit to the relay.

Correct... You could try swapping the relays or jumper 30-87 to check it.
Just remember, when you find 30 and 87 0n the relay, your looking at it upside down. It is usually the bottom left and top right opening.

https://cimg1.ibsrv.net/gimg/www.cob...d26e3ea853.jpg

Anyone know where I can get another one of these connectors? After visually inspecting the underside of the fuse box the ground wire coming out of one of the fan relays is burnt.

Does the fan work by trying what I mentioned? If it does, that is the issue since you said you had the power but not the ground from the PCM. NAPA carries Packard connectors or the Dealer.

Sorry, I didn't try what you mentioned. I did however go down to NAPA, get the proper connector put it all back together and it works now!

Thanks for the help guys.

All is good....