Ac on an 03 and up pcm?
#1
Ac on an 03 and up pcm?
I was told the A/C request on the 03+ computers is a serial data signal from HVAC control module, no wire input to trigger ac.
What exactly does this mean?I want ac.
What exactly does this mean?I want ac.
#2
Re: Ac on an 03 and up pcm?
I'm not an expert as to why A/C can't be controlled by a 58x ECM swap. Speartech doesn't offer it on their 58x harnesses, and they recommend vintage air. I kept the original 1984 design on my Trans Am. I added a vintage air trinary switch to replace the high pressure switch. The old style compressor had a high pressure switch. The sanden compressors do not.
#3
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Re: Ac on an 03 and up pcm?
CANBUS (Serial Data) is used to integrate PIM, BCM, and ECM control functions.
What Johnw999 is describing, is a work-around which allows operation of A/C but is not ECM controlled. This could result in stall conditions at stop light, and has no high rpm cut-off protection. As long as you have a good memory and keep the operating conditions in mind, you can have functioning A/C this way. You could program a higher idle rpm to avoid stall, and remember not to high rev with A/C on (we all have excellent right foot control, here ).
Trinary switch monitors psi and will cut-off compressor according to high and low presets.
Last edited by TEDSgrad; 11-08-2017 at 11:15 PM.
#5
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Re: Ac on an 03 and up pcm?
https://www.thirdgen.org/forums/ltx-...reen-blue.html
This is everything you need to get ac working with the stock hvac controls, high pressure switch, and ecm.
This is everything you need to get ac working with the stock hvac controls, high pressure switch, and ecm.