Marshall8hp
Well-Known Member
Air conditioning grant simply refers to whether the ECU has engaged the AC. If you have the AC off then the grant will be off, and vice versa.
Datatek
Well-Known Member
Well, that's wrong, when the aircon button is pressed the aircon is OFF.
i would try and recalibrate the flaps using the nano function. shd not be reading 232pc...
the a/c request is active low, and grant too.
the HEVAC needs to see the request conditions fulfilled and grant low to engage the clutch (or relay to the clutch, depending on MY). i had problems with my ECM not providing the grant signal in response to the request, so i have earthed the grant line to simulate the low, and the HEVAC still cycles on/ off properly based on all its other feeds
the HEVAC needs to see the request conditions fulfilled and grant low to engage the clutch (or relay to the clutch, depending on MY). i had problems with my ECM not providing the grant signal in response to the request, so i have earthed the grant line to simulate the low, and the HEVAC still cycles on/ off properly based on all its other feeds
That makes sense. The Thor and diesel are different from the GEMS. I seem to recall a guy in the States putting an LS1 engine in a GEMS and I think it was Marty that figured out the GEMS needs a signal from the engine ECU (possibly via BECM?) but the others just get an automated low signal from the BECM. It is over on RR.net somewhere from ten years or so ago. Pretty sure the solution was just to ground that wire.
Datatek
Well-Known Member
He said it's the blower not the flaps, but even so it should not read 232%. It's likely to be the blower motor drive transistor failed.
Good point
