Offroad Trailblazers and Envoys

Ac Pcm pin out

Something not working right?

by Jimw » Sat Feb 20, 2016 6:01 pm

Have been searching for an answer ... Is pin out 42 on the pcm c1 connector a ground reference or 12v for the ac relay .. This is on a 2003 i6 . Looking for an easy way to kick on and control efans when ac is active. I.e. Ground ...

Thanks for any input
Jimw
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by HawkeyeC25 » Sat Feb 20, 2016 9:57 pm

Powertrain Control Module (PCM) C1

Pin Wire Color Circuit No. Function

41 RED/BLK 380 A/C Refrigerant Pressure Sensor Signal
42 DK GRN/WHT 459 A/C Compresor Clutch Relay Control
43 DK BLU 2364 Cooling Fan Speed Signal
57 WHT/BLK 2366 Cooling Fan Clutch Control

Hope this helps!
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HawkeyeC25
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by HawkeyeC25 » Sat Feb 20, 2016 10:11 pm

Here's what I think you were asking for now that I re-read your question. The pin in the PCM pulls the wire to ground. The power for the relay comes out of the fuse block under the hood.
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ACRelay.gif
2003 TB AC Relay
2005 Trailblazer EXT LT V8 Lifted
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HawkeyeC25
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by Jimw » Sun Feb 21, 2016 1:18 am

The Efan kit I have from pcmofnc uses a ground to activate the kits relays .. I have the coolant side covered with the autometer in line hose kit and a switch that grounds on at 200f off at 185f .. Will verify that pin 42 is a found with multi meter tomorow .. Even if it is . Not sure I want the fans to cycle that much esp when cool out and using defrost.

Thanks for the reply,
JimW
Jimw
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Posts: 6
Joined: Sat Dec 26, 2015 11:10 pm
Location: Felton,DE
Name: James
Vehicle Year: 2003
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD w/ Limited Slip


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