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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2000 🢒 Montana 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Headlamps Inoperative - Low Beams

Headlamps Inoperative - Low Beams Domestic

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting System Diagnostic Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2
  1. Turn the headlamp switch to the HEAD position.
  2. Turn the headlamp dimmer switch to the LOW position.
  3. Use a test lamp in order to backprobe between C201 terminal E12 and ground.

Did the test lamp light?

--

Go to Step 3

Go to Step 4

3

Use a test lamp in order to backprobe between the underhood accessory junction block connector C2 terminal F8 and ground.

Did the test lamp light?

--

Go to Step 6

Go to Step 5

4

Inspect for the following conditions in CKT 12 between the headlamp dimmer switch and C201 terminal E13:

    • A faulty connection
    • An open

Is there a faulty connection or an open in CKT 12?

--

Go to Step 9

Go to Step 10

5

Repair the following conditions in CKT 12 between C201 terminal E12 and the underhood accessory junction block harness connector C2 terminal F4:

    • A faulty connection
    • An open

Is the repair complete?

--

Go to Step 12

--

6

Use a test lamp to backprobe between the underhood accessory junction block connector C3 terminal B8 and ground, and terminal A8 and ground.

Did the test lamp light at both terminals?

--

Go to Step 7

Go to Step 8

7
  1. Disconnect both of the headlamp connectors.
  2. Use a test lamp in order to frontprobe terminal B of each connector to ground.

Did the test lamp light at both connectors?

--

Go to Step 12

Go to Step 11

8

Replace the underhood accessory junction block. Refer to Relay/Fuse Center Replacement

Is the repair complete?

--

Go to Step 12

--

9

Repair a faulty connection or open in CKT 12.

Is the repair complete?

--

Go to Step 12

--

10

Replace the headlamp dimmer switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Is the repair complete?

--

Go to Step 12

--

11
  1. Repair an open in the circuit that would not light the test lamp.
  2. If the test lamp would light on one circuit, replace the headlamp on that circuit.

Is the repair complete?

--

Go to Step 12

--

12

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Headlamps Inoperative - Low Beams Export

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2
  1. Turn the headlamp switch to the HEAD position.
  2. Turn the headlamp dimmer switch to the LOW position.
  3. Use a test lamp in order to backprobe between C201 terminal E12 and ground.

Did the test lamp light?

--

Go to Step 3

Go to Step 4

3

Repair the following conditions in CKT 12 between C201 terminal E12 and the fuse block terminal C1:

    • An open
    • A poor connection

Has the repair been made and the system rechecked?

--

Go to Step 7

--

4

Inspect for the following conditions in CKT 12 between the headlamp dimmer switch and C201 terminal E12:

    • An open
    • A poor connection

Is there a poor connection or an open in CKT 12?

--

Go to Step 5

Go to Step 6

5

Repair the following conditions in CKT 12 between C201 terminal E12 and the headlamp dimmer switch:

    • A poor connection
    • An open

Has the repair been made and the system rechecked?

--

Go to Step 7

--

6

Replace the headlamp dimmer switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Has the repair been made and the system rechecked?

--

Go to Step 7

--

7

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2