henry172

iTrader: (2)

I installed the eficonnections 24x system on my 1997 TA last year. The car has never broken down on me since and it runs a lot better, but now that it has been so hot here in southern CA I have decided it is time to fix the air conditioning problem. I repined my own harness for the ls1 pcm, but I did not do anything with the lt1 Air conditioning wires. Does any one know if it is possible to run the lt1 a/c system with the ls1 pcm. If so where do I need to pin in the lt1 A/C wires on the ls1 pcm?

Thanks.

S10Wildside

With the exception of the temperature sensor in the A/C housing behind the dash of the LT1 car, the LT1 and LS1 A/C systems are electonically the same. The A/C temperature sensor is not used in an LS1 car. There is no purpose for it after an LS1 PCM conversion.

LS1 PCM...
BLUE 45 is 5V A/C Pressure Sensor (GRY wire)
RED 57 is Low Reference for A/C Pressure Sensor (BLK wire)
RED 14 is A/C Pressure Sensor signal (RED/BLK wire)

RED 17 is A/C Request from the switch on the dash (GRN/WHT wire)
RED 18 is 12V A/C Compressor Clutch Supply Voltage (GRN wire)
RED 43is A/C Clutch Relay Control (GRN/WHT wire)

Spend a few minutes with the LT1 PCM connector view, LS1 PCM connector view, and A/C schematics. It's easy to understand after you put a few minutes into it. Consider vehicle subscriptions at http://www.alldatadiy.com for the GM schematics.