my_99Z

iTrader: (4)

Hey all,

Just finished putting a refreshed LS6 motor into my 2005 V1. Everything is running great except the radiator fans are not coming on, not when the engine temp reaches 225, nor when the AC is activated. I have added a jumper to the fans to make sure the motors are working and they do. Checked the passenger side wiring harness and it is receiving 3.5Volts. The drivers side is receiving 0 voltage. Any help is appreciated.

I have replaced relays and the 30 amp fuses to start. Would a bad engine temperature sensor cause this? It is reading temperatures inside the car.

Anthony Toal

If it is reading in the car then it isnt your ECT. Where did you add the jumper to make the fans spin, both work correct?

my_99Z

iTrader: (4)

I jumpered from the battery directly to the fan motor. Yes both work when connected directly to the battery

Anthony Toal

Did you have a tune done to the car? I cant see why your fans wouldnt come on unless it was either relay or fuse related

my_99Z

iTrader: (4)

I bought the car and the motor was bad, the guy said it had blown the head gasket. Upon taking the car apart I was finding water in the intake and the combustion chambers of the heads. Then when I took the heads off, the #7 piston was sitting sideways in the cylinder with a broken rod, and #8 also had a broken rod. Looks almost like he hydrolocked the motor. He did mention the car had been tuned, but I can't imagine why someone would turn the fans off in the tune.


As a side question, IF the fans were turned off in the tune, would there be voltage going through the wiring harness to the fan motors? Because I'm only getting 3 to the passengers side, and 0 to the drivers side. Where are the ground locations for that side of the harness?

Thanks for the help

Anthony Toal

okay, so now knowing the extent of the damage, i would trace out the wires completely. you can do this by ohming from the relay to the harness end of the connector and see if you have an open loop or not

jmilz28

iTrader: (13)

Yep, if she took a drink...you gotta assume she went for a swim. Corrosion in wires, ugh! May that not be true!

my_99Z

iTrader: (4)

Okay so I narrowed it down to a bad fan motor. The low side would turn on when power was supplied directly to it via a battery source but it spun super slow. It ended up cooking the 30 AMP fuse I had just replaced. Took the fans out and cleaned both motors now the low side is working. Unfortunately I keep getting conflicting information as to the temperatures the fans are supposed to turn on at.
When the A/C is turned on, only the low fan comes on, I let the car get up to about 230F yesterday and the high speed didn't come on so I shut the car down.
What are normal temps for these fans to turn on at?