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For 1990-2009 cars only

Hazard Lamps Malfunction w/TT6

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

IGN E Fuse B+

3

3

--

--

HAZRD Fuse B+

3

3

--

--

DIC Switch Signal

1

1

1

--

Hazard Switch Signal

1

1

1

--

Front Turn Signal Lamp Control

3

3

3

--

Rear Turn SIgnal Lamp Control

3

3

3

--

Turn Signal/Hazard Flasher Module Control

4

4

4

--

DIC Switch Ground

--

2

--

--

Front Turn SIgnal Lamp Ground

--

3

--

--

Rear Turn Signal Lamp Ground

--

3

--

--

Turn Signal/Hazard Flasher Module Low Reference

--

4

--

--

1. Hazard Switch Malfunction

2. Hazard Malfunction

3. Turn SIgnal Malfunction

4. Turn Signal/Multifunction Switch Malfunction

Circuit/System Description

The IGN E fuse in the engine wiring harness junction block supplies Ignition positive voltage to the turn signal switch assembly. With the ignition switch in the RUN or START position, ignition positive voltage is connected through the turn signal and hazard switch assembly to the turn signal/hazard flasher module which is powered by the FLASHER fuse in the engine wiring harness junction block and is grounded at G201. When the turn signal switch is placed in either the left or right position, the circuit is complete from the turn signal/hazard flasher module to the turn signal lamps and to ground. The turn signal/hazard flasher module then sends an on-off voltage signal to either the left or right turn signals and their instrument panel cluster (IPC) indicator. When the hazard switch is pressed, all turn signal lamps will flash including both IPC turn indicators. The front turn signals are grounded at G103 and G107. The rear turn signals are grounded at G401 and G402.

Reference Information

Schematic Reference

Exterior Lights Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Exterior Lighting Systems Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Observe the left and right, front and rear turn signal lamps while the hazard switch is on.

If one or more of the lamps flash normally, refer to Turn Signal Lamps and/or Indicators Malfunction.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the turn signal/hazard flasher module.
  2. Verify that a test lamp illuminates between the B+ and the ground circuit terminal N.
  3. If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
  4. Verify that a test lamp illuminates between the B+ circuit terminal J and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. Connect the harness connector at the turn signal/hazard flasher module.
  7. Disconnect the harness connector at the DIC switch.
  8. Verify the hazard flashers are not on.
  9. If the hazard flashers are on, test the hazard switch signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the turn signal/hazard flasher module.
  10. Test for less than 5 ohms between the ground circuit terminal 5 and ground.
  11. If greater than the specified range, test the ground circuit for an open/high resistance.
  12. Install a 3A fused jumper wire between the hazard switch signal circuit terminal 2 and the ground circuit terminal 5. Verify the hazard flashers operate normal.
  13. If the hazard flashers do not operate, test hazard switch signal circuit for an open/high resistance. If the circuit tests normal, replace the turn signal/hazard flasher module.
  14. If all circuits test normal, replace the DIC switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Hazard and Turn Signal Flasher Replacement

Hazard Lamps Malfunction w/o TT6

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

IGN E Fuse B+

3

3

--

--

HAZRD Fuse B+

3

3

--

--

DIC Switch Signal

1

1

1

--

Hazard Switch Signal

1

1

1

--

Front Turn Signal Lamp Control

3

3

3

--

Rear Turn SIgnal Lamp Control

3

3

3

--

Turn Signal/Hazard Flasher Module Control

4

4

4

--

DIC Switch Ground

--

2

--

--

Front Turn SIgnal Lamp Ground

--

3

--

--

Rear Turn Signal Lamp Ground

--

3

--

--

Turn Signal/Hazard Flasher Module Low Reference

--

4

--

--

1. Hazard Switch Malfunction

2. Hazard Malfunction

3. Turn SIgnal Malfunction

4. Turn Signal/Multifunction Switch Malfunction

Circuit/System Description

The IGN E fuse in the engine wiring harness junction block supplies Ignition positive voltage to the turn signal switch assembly. With the ignition switch in the RUN or START position, ignition positive voltage is connected through the turn signal and hazard switch assembly to the turn signal/hazard flasher module which is powered by the FLASHER fuse in the engine wiring harness junction block and is grounded at G201. When the turn signal switch is placed in either the left or right position, the circuit is complete from the turn signal/hazard flasher module to the turn signal lamps and to ground. The turn signal/hazard flasher module then sends an on-off voltage signal to either the left or right turn signals and their instrument panel cluster (IPC) indicator. When the hazard switch is pressed, all turn signal lamps will flash including both IPC turn indicators. The front turn signals are grounded at G103 and G107. The rear turn signals are grounded at G401 and G402.

Reference Information

Schematic Reference

Exterior Lights Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Exterior Lighting Systems Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Observe the left and right, front and rear turn signal lamps while the hazard switch is ON.

If one or more of the lamps flash normally, refer to Turn Signal Lamps and/or Indicators Malfunction.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the turn signal/hazard flasher module.
  2. Test for less than 5.0 ohms between the ground circuit terminal E and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Verify that a test lamp illuminates between the B+ circuit terminal K and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. Connect the harness connector at the turn signal/hazard flasher module.
  7. Disconnect the harness connector at the DIC switch.
  8. Verify the hazard flashers are not on.
  9. If the hazard flashers are on, test the hazard switch signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the turn signal/hazard flasher module.
  10. Test for less than 5.0 ohms between the ground circuit terminal 5 and ground.
  11. If greater than the specified range, test the ground circuit for an open/high resistance.
  12. Install a 3A fused jumper wire between the hazard switch signal circuit terminal 2 and the ground circuit terminal 5. Verify the hazard flashers operate normal.
  13. If the hazard flashers do not operate, test hazard switch signal circuit for an open/high resistance. If the circuit tests normal, replace the turn signal/hazard flasher module.
  14. If all circuits test normal, replace the DIC switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Tail Lamp Replacement

Hazard and Turn Signal Flasher Replacement