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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Corvette 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Backup Lamps Inoperative

Backup Lamps Inoperative Automatic Transmission

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
  1. Turn ON the ignition, with the engine OFF.
  2. Depress and hold the brake pedal.
  3. Place the gear selector in the REVERSE position.
  4. Observe the backup lamps.

Do both backup lamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Is only one backup lamp inoperative?

Go to Step 7

Go to Step 4

4
  1. Turn OFF the ignition.
  2. Disconnect the reverse lamp relay. Refer to Relay Replacement in Wiring Systems.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the reverse lamp relay control side voltage supply circuit with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 8

5
  1. Turn OFF the ignition.
  2. Connect a test lamp between the reverse lamp relay control side voltage supply circuit and the backup lamp relay control circuit.
  3. Turn ON the ignition, with the engine OFF.
  4. Depress and hold the brake pedal.
  5. Place the gear selector in the REVERSE position.

Does the test lamp illuminate?

Go to Step 6

Go to Step 10

6
  1. Turn OFF the ignition.
  2. Connect a 15-amp fused jumper between the reverse lamp relay control side voltage supply circuit and the backup lamps supply voltage circuit.
  3. Turn ON the ignition, with the engine OFF.

Do the backup lamps illuminate?

Go to Step 11

Go to Step 7

7

Locate and repair an open or high resistance in the backup lamp voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 12

8

Locate and repair an open or high resistance in the reverse lamp relay control side voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 9

9

Inspect for poor connections at the C3 harness connector of the underhood fuse block. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 14

10

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 15

11

Inspect for poor connections at the reverse lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

12

Locate and repair an open or high resistance in the backup lamp ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

13

Replace the reverse lamp relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

14

Replace the underhood fuse block. Refer to Underhood Electrical Center or Junction Block Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 16

--

15

Replace the BCM. Refer to Body Control Module Replacement in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 16

--

16

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Backup Lamps Inoperative Manual Transmission

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
  1. Turn ON the ignition, with the engine OFF.
  2. Depress and hold the brake pedal.
  3. Shift the gear selector to the REVERSE position and then to the NEUTRAL position.
  4. Observe the backup lamps.

Do both backup lamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Is only one backup lamp inoperative?

Go to Step 7

Go to Step 4

4
  1. Turn OFF the ignition.
  2. Disconnect the reverse lamp relay. Refer to Relay Replacement in Wiring Systems.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the reverse lamp relay control side voltage supply circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 8

5
  1. Turn OFF the ignition.
  2. Connect a test lamp between the reverse lamp relay control side voltage supply circuit and the backup lamp relay control circuit.
  3. Turn ON the ignition, with the engine OFF.
  4. Depress and hold the brake pedal.
  5. Place the gear selector in the REVERSE position.

Does the test lamp illuminate?

Go to Step 6

Go to Step 9

6
  1. Turn OFF the ignition.
  2. Connect a 15-amp fused jumper between the reverse lamp relay control side voltage supply circuit and the backup lamp switched voltage supply circuit.
  3. Turn ON the ignition, with the engine OFF.

Do the backup lamps illuminate?

Go to Step 16

Go to Step 7

7

Locate and repair an open or high resistance in the backup lamp voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 15

8

Locate and repair an open or high resistance in the reverse lamp relay control side voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 13

9
  1. Turn OFF the ignition.
  2. Disconnect the reverse switch. Refer to Backup Lamp Switch Replacement in Manual Transmission - Tremec 6-Speed.
  3. Connect a 3-amp fused jumper between the reverse switch voltage supply circuit and the reverse lamp relay control circuit.
  4. Turn On the ignition, with the engine OFF.

Do the backup lamps illuminate?

Go to Step 12

Go to Step 10

10

Test the reverse switch voltage supply circuit for an open, high resistance, or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 11

11

Test the reverse lamp relay control circuit for an open, high resistance, or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 14

12

Inspect for poor connections at the harness connector of the reverse switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 18

13

Inspect for poor connections at the C 3 harness connector of the underhood fuse block. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 17

14

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 19

15

Locate and repair an open or high resistance in the backup lamp ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 20

--

16

Replace the reverse lamp relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 20

--

17

Replace the underhood fuse block. Refer to Underhood Electrical Center or Junction Block Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 20

--

18

Replace the reverse switch. Refer to Backup Lamp Switch Replacement in Manual Transmission - Tremec 6-Speed.

Did you complete the repair?

Go to Step 20

--

19

Replace the BCM. Refer to Body Control Module Replacement in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 20

--

20

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2