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Park, License, and Tail Lamps Always On

Park, License, and Tail Lamps Always On

Step Action Yes No
Schematic Reference: Exterior Lights Schematics (w/o V92/V4U/B9Q)  or Exterior Lights Schematics (Export)  or Exterior Lights Schematics (w/V92)  or Exterior Lights Schematics (w/ V4U/B9Q)  or Exterior Lights Schematics (Backup Lights) 
Connector End View Reference: Lighting Systems Connector End Views  or Body Control System Connector End Views
1 Did you perform the Lighting Systems Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Lighting Systems 
2
  1. Turn ON the ignition, with the engine OFF.
  2. Verify that the headlamp switch is in the OFF position.
Do either the marker, license or tail lamps remain illuminated?
Go to Step 3  Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
3 With a scan tool, observe the Park Lamp parameter in the Dash Integration Module (DIM) inputs data list.
Does the scan tool indicate that the Park Lamp parameter is off?
Go to Step 4  Go to Step 7 
4 With a scan tool, observe the Park Lamp Relay Output parameter in the Dash Integration Module (DIM) outputs data list.
Does the scan tool indicate that the Park Lamp Relay Output parameter is off?
Go to Step 5  Go to Step 15 
5
  1. Turn OFF the ignition.
  2. Disconnect the PRK LP relay.
  3. Turn ON the ignition, with the engine off.
Did the lamps turn off?
Go to Step 6  Go to Step 8 
6 Connect a test lamp between the supply voltage circuit of the PRK LP relay coil and the control circuit of the PRK LP relay.
Does the test lamp illuminate?
Go to Step 12  Go to Step 14 
7
  1. Turn OFF the ignition.
  2. Disconnect the headlamp switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Park Lamp parameter.
Does the scan tool indicate that the Park Lamp parameter is off?
Go to Step 13  Go to Step 11 
8
  1. Turn OFF the ignition.
  2. Disconnect the harness connector of the DIM (C3).
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the backlight lamps control circuit and a good ground.
Does the test lamp illuminate?
Go to Step 19  Go to Step 9 
9
  1. Turn OFF the ignition.
  2. Reconnect the harness connector of the DIM (C3).
  3. Turn ON the ignition, with the engine OFF.
  4. Disconnect the LP PK R fuse.
Do any of the lamps powered by the LP PK R fuse remain on?
Go to Step 16  Go to Step 10 
10 Disconnect the LP PK L fuse.
Do any of the lamps powered by the LP PK L fuse remain on?
Go to Step 17  Go to Step 18 
11 Test for a short to ground in the park lamp switch on signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 23  Go to Step 15 
12 Test for a short to ground in the park lamp relay control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 23  Go to Step 15 
13 Inspect for poor connections at the harness connector of the headlamp 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 23  Go to Step 20 
14 Inspect for poor connections at the PRK LP 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 23  Go to Step 21 
15 Inspect for poor connections at the harness connector of the Dash Integration Module (DIM). 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 23  Go to Step 22 
16 Repair a short to voltage in the right park lamp supply voltage circuit.
Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 23  -
17 Repair a short to voltage in the left park lamp supply voltage circuit.
Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 23  -
18 Repair a short to voltage in the instrument panel lamp fuse supply voltage-1 circuit.
Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 23  -
19 Repair a short to battery positive voltage in the backlight lamps control circuit.
Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 23  -
20 Replace the headlamp switch. Refer to Headlamp Switch Replacement .
Did you complete the replacement?
Go to Step 23  -
21 Replace the PRK LP relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.
Did you complete the replacement?
Go to Step 23  -
22 Replace the DIM. Refer to Dash Integration Module Replacement in Body Control System.Did you complete the replacement? Go to Step 23  -
23 Operate the system in order to verify the repair.
Did you correct the condition?
System OK Go to Step 2