GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Exterior Lights System Check?

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Go to Step 2

Go to Exterior Lights System Check

2

  1. Disconnect the stoplamp/BTSI switch connector C2.
  2. Connect a J 39200 digital multimeter (DMM) between the stoplamp/BTSI switch connector C2 cavity A (ORN) and ground.

Is the voltage within the specified range?

10-15 V

Go to Step 3

Go to Step 6

3

Connect a fused jumper between the stoplamp/BTSI switch connector C2 cavity A (ORN) and cavity B (LT BLU).

Do all of the stoplamps illuminate?

--

Go to Step 4

Go to Step 5

4

Replace the stoplamp/BTSI switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Is the stoplamp/BTSI switch replacement complete?

--

Go to Exterior Lights System Check

--

5

Repair the open in CKT 20 (LT BLU) between the stoplamp/BTSI switch and the rear junction block. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Exterior Lights System Check

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6

Repair the open in CKT 640 (ORN) between the underhood junction block and the stoplamp/BTSI switch. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Exterior Lights System Check

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