Can somebody please confirm/comment on (e.g., re-fine) my understanding of how the Subaru A/C compressor and ECU work. As a background, I'm in the middle of re-wiring a Subaru harness to work with a VW vanagon, so I'm trying to figure out exactly how the Subaru wires and Subaru components will integrate with my Vanagon A/C wire and dash controls.
Here's my understanding of Subaru >>
When the driver pushes the A/C ON button:
1. A signal is sent to the A/C compressor to turn ON.
2. The A/C compressor get its power from the belt system (not a wire).
3. A signal is also sent to the ECU to tell it that A/C is ON. This allows the brains to control idling differently while AC is on vs. off.
The process is the opposite when the driver pushes the OFF button on the dash.
So, there are two wires.
One goes to the ECU
One goes to the A/C compressor
Is this a correct understanding of how the Subaru A/C system works, in a nutshell?
So, I'm thinking I don't need to wire any pwr wires to the A/C comp. But, I do need to wire the signal wires up.
Are the two wires the same gauge? Seems like a simple signal could be carried on a 18 AWG wire easy enough.
Edited by coclimber, 05 May 2014 - 11:53 AM.