high fan speed signal wire

[9c1vs]

Just wondering which wire to run my trigger wire for my thermo fans to? I can see which wire back at the ecu, but wondering if there is a wire in the engine bay I can hook up to in order to trigger the relays. Cheers

[9c1vs]

Also, my relay is set to trigger with an earth because that is how the haltech triggers it. Does the c2 wire act like this? I traced the blue/white wire to the harness attached to my condenser fan. I can not seem to get my condenser fan running at all actually, with ac on and with high speed fan showing on my tuner pro dash board. I am using an nv ram and ose 12p to tune. Cheers

[VL400]

Correct, the fan is triggered by an earth. Wiring diagrams are here for VR V8, pretty much the same as a VS .. http://pcmhacking.net/forums/viewtopic. ... =338#p3306

If you put the ECU in diagnostic mode (bridge pins 5 and 6 of the diagnostic connector) to flash out fault codes via the CEL the fan is turned on.

[9c1vs]

Cheers for the link! I can see where it all hooks up now. However, it appears I have a bit of an issue. Basically, the fan would not switch on in diagnostic mode, so I did a couple of checks. Firstly, I swapped the nvram for a spare memcal and still no go. I then swapped back to the nvram and clicked the reset high fan speed button as suggested in another post. Still no go. finally, I threw the Haltech back on and all runs fine.

As the Haltech is running the fan, I have ruled out wiring and relays as the issue. Given the fan would not switch on with either the memcal and I reset the fan operation malf code on the nvram, I can't see how it would be in the tune. The only thing I can think of is that there is a problem on the main circuit board of the ecu and the signal is not getting to pin c1. However, it is not quite that simple as when I switch the air con off, the fan comes on for a few moments and then switches back off. So something must be coming through wire c1, but it is not working properly or something!

In fact, come to think of it, I do remember that the air con fan did not always come on before I switched to the haltech. However, that was ages ago so I can't really remember. To me it is pointing to a hardware issue with my ecu?

[vlad01]

sounds like what i had which overheated my engine as result. i replaced the ecu and it was fine

[9c1vs]

Yeah going back to before the Haltech I had the clutch fan on so it wasn't an issue for overheating. As for the past few days I have just been earthing out the fans and running them constantly.