Thermo fan/s

[Asho88]

Hi all preparing for a show going over everything anyway last year the clutch fan wasn’t able to keep up with the heat/traffic so I’ve opted to use a thermo fan what would be the best way of controlling it the 808s are capable of controlling them aren’t they? They use a thermo on the v6 just can’t see any thermo wires in the pin out of the ECU. Cheers

[antus]

If you look at the OSE 12P ECM Pinouts.txt in the OSE 12P zip file package pin C1 type digital output is High Speed Fan Output.

It switches the low side of the relay coil for fan power.

[Asho88]

Yeah I found a Pin out and realised that was the one I’m just playing around with it it patched part of a body loom in so have a relay with pins 87 & 30 receiving battery power it’s a the fan wiring for the body loom so I snipped a blue white wire (which should be out put from ecu and a pink wire which would obviously only leave input to the fans. But does this provide a switched ground? Just trying to mimic it before I go to far the relay clicks but the fan don’t turn on the fan is fine works straight off the battery

[antus]

none of what you said makes sense to me as someone not looking at the loom. But the relay has 2 pins with a coil between them that switches on when power is going through the relay coil. So one side of that coil should have B+ and the other side goes to the ecm pin. Look at a VR V6 manual wiring diagram for examples.

[Asho88]

Yeah it’s weird that 1. It has two battery supplies and 2. The way it’s wired isn’t how any diagrams show. It’s a part of a standard VN v6 body loom I just used what I need to wire it up without having to butcher the engine loom. I kept the fan relay because I knew I’d look at a thermo fan down the track. It’s wired as factory apart from the two snipped wires which is the blue white (should be pin C1 from the ecu which is I believe a switched ground and a pink wire which I believe was meant to wire into the fan. But maybe I’m mixed up. I tried just rigging it up with another relay and doing as above to battery power sources, a ground and a fan signal to mimick it before hard wiring but got nothing other then a click from the relay.

[Asho88]

Wiring is as pictured

[antus]

well then its relay 85 to ecm C1

[Asho88]

Yeah that’s what I was thinking but been playing around with it and doesn’t seem to fire the fan up it’s really odd. Seems C1 is meant to be a switched earth but it’s earthing even with the car off which is probably normal just can’t understand why the fan won’t turn on. (I’ve changed the settings to 10 degrees) it lights up on the tuner pro dash as high fan on very odd.

[antus]

the settings can be confusing. recommend stock. hook it up and remove rw on nvram for safety and remove nvram so its in backup mode and confirm it turns on that way. note speed settings are max not min speed, idea is that above X speed you have enough airflow so fan turns off. But until you think about it you tend to think its a min speed. Other settings may be confusing too. Use the logs to see if fan is supposed to be on before assuming a problem.

[antus]

also 2 battery connections are 1 for low current coil side of the relay for the switching signal (ecm on ground side) and other is for high current power to the fan when the relay turns on.