To the top of the document
Spark
   
GMDE Start Page Load static TOC Load dynamic TOC Help?

Indicator Lamps and/or Indicators Malfunction

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

Indicator/Hazard Flasher Module B+

1, 2

1, 2

--

--

Indicator/Hazard Flasher Module Ground

1, 2

1, 2

Left Front Turn Signal Lamp Supply Voltage

1

1

3

--

Right Front Turn Signal Lamp Supply Voltage

2

2

4

--

Left Rear Turn/Brake Lamps Supply Voltage

1

1

3

--

Right Rear Turn/Brake Lamps Supply Voltage

2

2

4

--

1. Left indicator is inoperative

2. Right indicator is inoperative

3. Left indicator is always ON

4. Right indicator is always ON

Circuit/System Description

Indicator/multi-function switch provides a pulsating voltage to the indicator lamps with the switch in the left or right position. The indicator lamps may only be activated with the ignition switch in the ON or START position. When the indicator/multifunction switch is placed in either the TURN RIGHT or TURN LEFT position, the indicator/hazard flasher module then applies a pulsating voltage to the front and rear indicator lamps and instrument cluster indicators through their respective voltage supply circuits.

Circuit/System Verification

Ignition ON, observe the indicator lamps while switching the Indicator/Multi-Function Switch between the left and right positions. The lamps should turn ON and OFF.

If the lamps do not turn ON and OFF when changing between the commanded states, refer to Indicator/Hazard Flasher Module Malfunction.
If the lamps do turn ON and OFF between the commanded states and the instrument cluster indicator indicators are inoperative, refer to Indicator Indicators Malfunction.

Circuit/System Testing

Indicator/Hazard Flasher Module Malfunction

  1. Ignition OFF, disconnect the wiring harness plug at the K72 Indicator/Hazard Flasher Module.
  2. Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal 8.
  3. If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between B+ circuit terminal 2 and ground.
  5. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace K72 Indicator/Hazard Flasher Module.

Indicator Lamps Malfunction

  1. Ignition OFF, disconnect the harness connector at the inoperative indicator lamp.
  2. Disconnect the negative terminal of the C1 Battery.
  3. Ignition OFF, exterior lamps OFF, test for less than 5 Ω between the appropriate ground circuit terminal listed below and ground.
  4. • Indicator Lamp - Left Front ground circuit terminal 2
    • Indicator Lamp - Right Front ground circuit terminal 2
    • Indicator Lamp - Left Rear ground circuit terminal
    • Indicator Lamp - Right Rear ground circuit terminal
    If greater than the specified range, test the ground circuit for an open/high resistance.
  5. Reconnect the negative terminal to the C1 Battery.
  6. Connect a test lamp between the appropriate control circuit terminal listed below and ground.
  7. • Indicator Lamp - Left Front control circuit terminal 1
    • Indicator Lamp - Left Rear control circuit terminal
    • Indicator Lamp - Right Rear control circuit terminal
  8. Command the appropriate Indicator Lamp ON and OFF with indicator/Multi-Function Switch. The test lamp should turn ON and OFF when changing between the commanded states.
  9. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K72 Indicator/Hazard Flasher Module.
    If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K72 Indicator/Hazard Flasher Module.
  10. If all circuits test normal, replace the appropriate indicator lamp assembly.

Indicator Indicators Malfunction

Ignition ON, command the All Indicators ON and OFF with the hazard warning switch, verify both turn signal indicators change between turn ON and OFF.

If both turn signal indicators changes between illuminate and not illuminate during the test, replace the K72 Indicator/Hazard Flasher Module.
If one or both indicator indicators do not illuminate during the test or remain illuminated at all times, replace the P16 Instrument Cluster.

Component Testing

Static Test - Indicator Switch

  1. Ignition OFF, disconnect the harness connector at the S78 Indicator/Multifunction Switch.
  2. Remove S78 Indicator/Multifunction Switch.
  3. Test for greater than 500 K Ω between terminal 1 (X1) and terminal 2 (X1).
  4. If less than the specified value, replace the S78 Indicator/Multifunction Switch.
  5. Test for greater than 500 K Ω between terminal 3 (X1) and ground terminal 2 (X1).
  6. If less than the specified value, replace the S78 Turn Signal/Multi-Function Switch
  7. Push the S78 Indicator/Multifunction Switch turn left. Test for less than 5 Ω between signal terminal 1 (X1) and ground terminal 2 (X1).
  8. If greater than the specified value, replace the S78 Indicator/Multifunction Switch.
  9. Push the S78 Indicator/Multifunction Switch turn right. Test for less than 5 Ω between signal terminal 3 (X1) and ground terminal 2 (X1).
  10. If greater than the specified value, replace the S78 Indicator/Multifunction Switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Headlamp Replacement
    •  Tail Lamp Replacement
   


© Copyright Chevrolet. All rights reserved