AC switch always on Evoscan (Chrome V2)

[Dougal]

Hey All,

Wondering how I can turn the AC switch off in my ROM so its off in Evoscan.

Basically I have a feeling that its playing around with the ISC Steps count (AC bump ISCV?)

I don't have AC in my car it was deleted.

If this being on has no bearing on ISC steps then i'll move on but if it does I'm thinking its possibly stopping my ECU from having the idle position switch turned on?

I'm troubleshooting a acceleration and deceleration jerkiness that has in the past has shown some knock (9 counts) at that point.

ISC affected by AC switch.jpg


Thanks

[Dougal]

Hey All,

Wondering how I can turn the AC switch off in my ROM so its off in Evoscan.

Basically I have a feeling that its playing around with the ISC Steps count (AC bump ISCV?)

I don't have AC in my car it was deleted.

If this being on has no bearing on ISC steps then i'll move on but if it does I'm thinking its possibly stopping my ECU from having the idle position switch turned on?

I'm troubleshooting a acceleration and deceleration jerkiness that has in the past has shown some knock (9 counts) at that point.

ISC affected by AC switch.jpg


Thanks

Well I can put the Idle switch issue to rest now as I have my idle switch working now.
I had outdated evoscan formula and now it shows the idle switch doing its thing. Found the formula in one of Gregs posts.
Still have A/C switch showing.

Really would like to just switch it off?

Anyone know if this is contained somewhere in the Chrome V2 ROM and if it can be disabled?

[stealthee]

Is your heater in defrost mode? If so then your AC switch will be on at that point.

[Greg E]

No way to disable it in the ROM without a major rewrite. Best pull the pin from the ECU harness if you can't track down where it's grounded in your climate controls.

[Dougal]

No way to disable it in the ROM without a major rewrite. Best pull the pin from the ECU harness if you can't track down where it's grounded in your climate controls.

Ok that I can do.

Thanks

[mojo3120]

No way to disable it in the ROM without a major rewrite. Best pull the pin from the ECU harness if you can't track down where it's grounded in your climate controls.

Which pin controls this? I've got the same problem, AC switch always shows on. Removed AC switch 1 and AC switch 2 from harness and switch still shows on. Is it the compressor relay pin?

[mojo3120]

I think that switch may just read backwards from the rest of them (1=off, 0=on). I hooked up a spare ecu on a bench....when AC switch 1 pin is floating, it reads 1, when it's pulled high it reads 0. Also, backprobing that pin in the car and applying 12V kicks up the idle.

Can anyone with a working AC verify this?