Page 481 of 4284

Symptom:
HEADLAMP SWITCH SHORT TO GROUND
When Monitored and Set Condition:
HEADLAMP SWITCH SHORT TO GROUND
When Monitored: Ignition ON
Set Condition: A Sensor voltage is below 0.488 volts for more than 0.0625 seconds.
POSSIBLE CAUSES
HEADLAMP SWITCH SHORTED
INTERMITTENT WIRING AND CONNECTORS
HEADLAMP SWITCH MUX CIRCUIT SHORT TO GROUND
HEADLAMP SWITCH MUX RETURN CIRCUIT SHORT TO GROUND
HEADLAMP SWITCH MUX CIRCUIT SHORT TO MUX RETURN CIRCUIT
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, record and erase DTC's.
Turn the headlamps to the ON position.
With the DRBIIIt, read DTCs.
Does the DRBIIItdisplay HEADLAMP SWITCH SHORT TO GROUND?All
Ye s®Go To 2
No®Go To 6
2 Turn the ignition off.
Disconnect the Headlamp Switch harness connector.
Turn the ignition on.
With the DRB, select Body, Body Control Module and read the Headlamp Switch
Sensor voltage..
Does the DRB display a Headlamp Switch Voltage of more than 4.8 volts?All
Ye s®Replace the Headlamp Switch in accordance with the Service
Information.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
3 Turn the ignition off to the lock position.
Disconnect the Body Control Module harness connector.
Disconnect the Headlamp Switch harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the Headlamp Switch MUX circuit.
Is the resistance less than 5.0 ohms?All
Ye s®Repair the Headlamp Switch MUX Circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 4
452
EXTERIOR LIGHTING
Page 482 of 4284

TEST ACTION APPLICABILITY
4 Turn the ignition off to the lock position.
Disconnect the Body Control Module harness connector.
Disconnect the Headlamp Switch harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between the Headlamp Switch MUX Return circuit and the
Headlamp Switch MUX circuit.
Is the resistance less than 5.0 ohms?All
Ye s®Repair the Headlamp Switch MUX circuit for a short to the
Headlamp Switch MUX Return circuit.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 5
5 Turn the ignition off to the lock position.
Disconnect the Body Control Module harness connector.
Disconnect the Headlamp Switch harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the Headlamp Switch MUX Return
circuit.
Is the resistance less than 5.0 ohms?All
Ye s®Repair the Headlamp Switch MUX Return Circuit for a short to
ground.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Body Control Module in accordance with the Service
Information.
Perform BODY VERIFICATION TEST - VER 1.
6 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wiring while checking for shorts and open circuits.
Were there any problems found?All
Ye s®Repair as necessary.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
453
EXTERIOR LIGHTING
HEADLAMP SWITCH SHORT TO GROUND ÐContinued
Page 483 of 4284

Symptom:
HIGH BEAM SWITCH INPUT OPEN
When Monitored and Set Condition:
HIGH BEAM SWITCH INPUT OPEN
When Monitored: Ignition On.
Set Condition: When voltage is below 4.8 volts.
POSSIBLE CAUSES
INTERMITTENT CONDITION
MULTIFUNCTION SWITCH
HIGH BEAM SWITCH MUX CIRCUIT OPEN
MULTIFUNCTION SWITCH MUX RETURN CIRCUIT OPEN
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, clear all BCM DTC's.
Turn the Headlamps On.
Actuate the High Beams.
With the DRBIIIt, read the DTC information.
Does the DRBIIItread: High Beam Switch Input Open?All
Ye s®Go To 2
No®The condition that caused the symptom is currently not present.
Inspect the related wiring for a possible intermittent condition.
Look for any chafed, pierced,pinched, or partially broken wires.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off
Disconnect the Multifunction Switch harness connector.
Connect a jumper wire between the High Beam Switch MUX circuit and the
Multifunction Switch MUX Return circuit in the Multifunction Switch connector.
Turn the ignition on.
With the DRBIIIt, read the Multifunction Switch voltage.
Is the display voltage below 0.5 volts?All
Ye s®Replace the Multifunction Switch.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
454
EXTERIOR LIGHTING
Page 484 of 4284

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the Body Control Module harness connector.
Disconnect the Multifunction Switch harness connector.
Measure the resistance of the High Beam Switch MUX circuit from the Body Control
Module connector to the Multifunction Switch harness connector.
Is the resistance above 5.0 ohms?All
Ye s®Repair the High Beam Switch MUX circuit for an open.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 4
4 Turn the ignition off.
Disconnect the Body Control Module harness connector.
Disconnect the Multifunction Switch harness connector.
Measure the resistance of the Multifunction Switch MUX Return circuit from the
Body Control Module connector to the Multifunction Switch harness connector.
Is the resistance above 5.0 ohms?All
Ye s®Repair the Multifunction Switch MUX Return circuit for an open.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
455
EXTERIOR LIGHTING
HIGH BEAM SWITCH INPUT OPEN ÐContinued
Page 485 of 4284

Symptom:
HIGH BEAM SWITCH INPUT SHORT
When Monitored and Set Condition:
HIGH BEAM SWITCH INPUT SHORT
When Monitored: Ignition On.
Set Condition: When voltage is below 0.488 volts.
POSSIBLE CAUSES
INTERMITTENT CONDITION
MULTIFUNCTION SWITCH
HIGH BEAM SWITCH MUX CIRCUIT SHORT TO GROUND
HIGH BEAM SWITCH MUX SHORT TO MUX RETURN CIRCUIT
MULTIFUNCTION SWITCH MUX RETURN CIRCUIT SHORT TO GROUND
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, clear all BCM DTC's.
Actuate the High Beams.
With the DRBIIIt, read the DTC information.
Does the DRBIIItread: High Beam Switch Input Short?All
Ye s®Go To 2
No®The condition that caused the symptom is currently not present.
Inspect the related wiring for a possible intermittent condition.
Look for any chafed, pierced,pinched, or partially broken wires.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Multifunction Switch harness connector.
Turn the ignition on.
With the DRBIIIt, read the Multifunction Switch voltage.
Is the voltage above 4.8 volts?All
Ye s®Replace the Multifunction Switch.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
3 Turn the ignition off.
Disconnect the Body Control Module harness connector.
Disconnect the Multifunction Switch Harness connector.
Measure the resistance between the High Beam Switch MUX circuit and ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the High Beam Switch MUX circuit for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 4
456
EXTERIOR LIGHTING
Page 486 of 4284
TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the Body Control Module harness connector.
Disconnect the Multifunction Switch harness connector.
Measure the resistance between the Multifunction Switch MUX Return circuit and
the High Beam Switch MUX circuit.
Is the resistance below 5.0 ohms?All
Ye s®Repair the High Beam Switch MUX circuit for a short to the
Multifunction Switch MUX Return circuit.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 5
5 Turn the ignition off.
Disconnect the Body Control Module harness connector.
Disconnect the Multifunction Switch harness connector.
Measure the resistance between the Multifunction Switch MUX Return circuit and
ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Multifunction Switch MUX Return circuit for a short
to ground.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
457
EXTERIOR LIGHTING
HIGH BEAM SWITCH INPUT SHORT ÐContinued
Page 487 of 4284

Symptom:
LEFT FRONT TURN SIGNAL OUTPUT OPEN
When Monitored and Set Condition:
LEFT FRONT TURN SIGNAL OUTPUT OPEN
When Monitored: Ignition On.
Set Condition: When output voltage status is LOW.
POSSIBLE CAUSES
INTERMITTENT CONDITION
GROUND CIRCUIT
TURN SIGNAL LAMP
LEFT TURN SIGNAL OUTPUT CIRCUIT OPEN
LEFT FRONT TURN SIGNAL DRIVER CIRCUIT OPEN
BODY CONTROL MODULE
INTELLIGENT POWER MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, clear all BCM DTC's.
Actuate the Turn Signals.
With the DRBIIIt, read the DTC information.
Does the DRBIIItread: Left Front Turn Signal Output Open?All
Ye s®Go To 2
No®The condition that caused the symptom is currently not present.
Inspect the related wiring for a possible intermittent condition.
Look for any chafed, pierced,pinched, or partially broken wires.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off
Disconnect the Left Front Turn Signal harness connector.
Using a 12-volt test light connected to 12-volts, check the ground circuit.
Does the test light illuminate brightly?All
Ye s®Go To 3
No®Repair the Ground Circuit.
Perform BODY VERIFICATION TEST - VER 1.
458
EXTERIOR LIGHTING
Page 488 of 4284

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the Left Turn Signal Lamp connector.
Turn the ignition on.
Turn the Left Turn Signal on.
Using a 12-volt test light connected to ground, check the Left Front Turn Signal
Output circuit.
Does the test light illuminate brightly?All
Ye s®Replace the Turn Signal Lamp.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 4
4 Turn the ignition off.
Disconnect the IPM C2 harness connector.
Measure the resistance of the Left Front Turn Signal Output Circuit and ground.
Is the resistance above 5.0 ohms?All
Ye s®Repair the Left Front Turn Signal Output Circuit for an open
condition.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 5
5 Turn the ignition off.
Disconnect the Body Control Module C2 connector.
Measure the resistance of the Left Front Turn Signal Driver Circuit to ground.
Is the resistance above 5.0 ohms?All
Ye s®Repair the Left Front Turn Signal Driver Circuit for an open
condition.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 6
6 Turn the ignition off.
Disconnect the Body Control Module C2 harness connector.
Disconnect the IPM C9 harness connector.
Measure the resistance of the Left Front Turn Signal Driver Circuit and ground.
Is the resistance below 5.0 ohms?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the Intelligent Power Module.
Perform BODY VERIFICATION TEST - VER 1.
459
EXTERIOR LIGHTING
LEFT FRONT TURN SIGNAL OUTPUT OPEN ÐContinued