GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

  1. Turn the ignition switch to RUN.
  2. Backprobe the air dryer with a test lamp from terminal A of the chassis ground.

Did the test lamp light?

Go to Step 2

Go to Step 3

2

Repair the open in CKT 150 (BLK) between terminal B of the inoperative components and G 404.

Do both the air dryer and the moisture ejector heater operate?

System OK

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3

Repair the open in CKT 341 (BRN), CKT 139, or CKT 145 (PNK) between the IP fuse block and terminal A of the components.

Do both the air dryer and the moisture ejector heater operate?

System OK

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