Exterior Lights (Body Control Module and Relay Control Module) Input Test
NOTE:
Make sure the fuses associated with the system is OK.
If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A.

Body Control Module

1.
Turn the vehicle to the OFF (LOCK) mode.

2.
Disconnect body control module connectors.
Body Control Module Connector A (14P) (female terminals):
Body Control Module Connector C (28P) (female terminals):
Body Control Module Connector E (24P) (female terminals):

3.
Inspect the connector and socket terminals to be sure they are all making good contact:
If the terminals are bent, loose, or corroded, repair them as necessary, and recheck the system.
If the terminals are OK, go to step 4.

4.
Reconnect the connectors to the body control module, do the following input tests:
If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, go to step 5.

Cavity
Wire
Test condition
Test: Desired result
Possible cause if desired result is not obtained
C27
WHT
Under all conditions
Measure the voltage to ground:
There should be battery voltage.
An open or high resistance in the wire
E1
BLU
Vehicle ON mode
Measure the voltage to ground:
There should be battery voltage.
An open or high resistance in the wire
A2
BLK
In all power modes
Measure the voltage to ground:
There should be less than 0.2 V.
Poor ground (G401)
An open or high resistance in the wire
A8
BLK
In all power modes
Measure the voltage to ground:
There should be less than 0.2 V.
Poor ground (G401)
An open or high resistance in the ground wire
C10
•
C3
PNK
•
BLK
Combination light switch OFF
Measure the voltage between terminals C10 and C3:
There should be less than 0.2 V.
Faulty combination light switch
An open or high resistance in the wire
Combination light switch in any position other than OFF
Measure the voltage between terminals C10 and C3:
There should be battery voltage.
Faulty combination light switch
A short to ground in the wire
C11
•
C3
GRY
•
BLK
Combination light switch (PARKING position) ON
Measure the voltage between terminals C11 and C3:
There should be less than 0.2 V.
Faulty combination light switch
An open or high resistance in the wire
Combination light switch OFF
Measure the voltage between terminals C11 and C3:
There should be battery voltage.
Faulty combination light switch
A short to ground in the wire
C9
•
C3
PNK
•
BLK
Combination light switch (headlight) ON
Measure the voltage between terminals C9 and C3:
There should be less than 0.2 V.
Faulty combination light switch
An open or high resistance in the wire
Combination light switch OFF
Measure the voltage between terminals C9 and C3:
There should be battery voltage.
Faulty combination light switch
A short to ground in the wire
C7
•
C3
GRN
•
BLK
Combination light switch lever pulled (Passing)
Measure the voltage between terminals C7 and C3:
There should be less than 0.2 V.
Faulty combination light switch
An open or high resistance in the wire
Combination light switch lever released (OFF)
Measure the voltage between terminals C7 and C3:
There should be battery voltage.
Faulty combination light switch
A short to ground in the wire
C8
•
C3
LT BLU
•
BLK
Combination light switch (Dimmer) in high beam position
Measure the voltage between terminals C8 and C3:
There should be less than 0.2 V.
Faulty combination light switch
An open or high resistance in the wire
Combination light switch (Dimmer) in low beam position
Measure the voltage between terminals C8 and C3:
There should be battery voltage.
Faulty combination light switch
A short to ground in the wire
C6*
•
C3
PUR
•
BLK
Front fog light switch ON
Measure the voltage between terminals C6 and C3:
There should be less than 0.2 V.
Faulty combination light switch
An open or high resistance in the wire
Front fog light switch OFF
Measure the voltage between terminals C6 and C3:
There should be battery voltage.
Faulty combination light switch
A short to ground in the wire
*: With front fog light

Relay Control Module

5.
Turn the vehicle to the OFF (LOCK) mode.

6.
Disconnect relay control module connectors.
Relay Control Module Connector A (6P) (female terminals):
Relay Control Module Connector B (10P) (female terminals):
Relay Control Module Connector C (18P) (female terminals):

7.
Inspect the connector and socket terminals to be sure they are all making good contact:
If the terminals are bent, loose, or corroded, repair them as necessary, and recheck the system.
If the terminals are OK, go to step 8.

8.
With the connectors still disconnected, do the following input tests:
If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, go to step 9.

Cavity
Wire
Test condition
Test: Desired result
Possible cause if desired result is not obtained
B4
•
B8
ORN
•
PUR
Under all conditions
Connect terminal B4 and B8 with a jumper wire:
The left headlight (low beam) should come on.
Blown bulb or faulty LED
Poor ground (G351) or an open in the ground wire
An open or high resistance in the wire
C5
•
C11
RED
•
GRN
Under all conditions
Connect terminal C5 and C11 with a jumper wire:
The right headlight (low beam) should come on.
Blown bulb or faulty LED
Poor ground (G251) or an open in the ground wire
An open or high resistance in the wire
B4
•
B5
ORN
•
BRN
Under all conditions
Connect terminal B4 and B5 with a jumper wire:
The left headlight (high beam) should come on.
Blown bulb or faulty LED
Poor ground (G351) or an open in the ground wire
An open or high resistance in the wire
C5
•
C3
RED
•
GRY
Under all conditions
Connect terminal C5 and C3 with a jumper wire:
The right headlight (high beam) should come on.
Blown bulb or faulty LED
Poor ground (G251) or an open in the ground wire
An open or high resistance in the wire
C5
•
C1
RED
•
PUR
Under all conditions
Connect terminal C5 and C1 with a jumper wire:
The left front parking light, left taillight, left inner taillight, and license plate lights should come on.
Faulty LED
Poor ground (G351, G505) or an open in the ground wire
An open or high resistance in the wire
B4
•
B10
ORN
•
RED
Under all conditions
Connect terminal B4 and B10 with a jumper wire:
The right front parking light, right taillight, and right inner taillight should come on.
Faulty LED
Poor ground (G251, G504) or an open in the ground wire
An open or high resistance in the wire
C5
•
C8
RED
•
YEL
Under all conditions
Connect terminal C5 and C8 with a jumper wire:
The left daytime running light should come on.
Faulty LED
Poor ground (G351) or an open in the ground wire
An open or high resistance in the wire
B4
•
B3
ORN
•
PNK
Under all conditions
Connect terminal B4 and B3 with a jumper wire:
The right daytime running light should come on.
Faulty LED
Poor ground (G251) or an open in the ground wire
An open or high resistance in the wire
C4
YEL
Under all conditions
Connect terminal to ground with a jumper wire:
The front fog lights should come on.
Faulty front fog light relay
Blown bulb
Poor ground (G251) or an open in the ground wire
An open or high resistance in the wire

9.
Reconnect the connectors to the relay control module, do the following input tests:
If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, go to step 10.

Cavity
Wire
Test condition
Test: Desired result
Possible cause if desired result is not obtained
A1
RED
Under all conditions
Measure the voltage to ground:
There should be battery voltage.
An open or high resistance in the wire
A4
LT GRN
Vehicle ON mode
Measure the voltage to ground:
There should be battery voltage.
An open or high resistance in the wire
A6
BRN
In all power modes
Measure the voltage to ground:
There should be less than 0.2 V.
Poor ground (G251)
An open or high resistance in the wire
C15
BRN
In all power modes
Measure the voltage to ground:
There should be less than 0.2 V.
Poor ground (G251)
An open or high resistance in the ground wire
C10
PNK
Combination light switch (headlight) ON
Measure the voltage to ground:
There should be less than 0.2 V.
Faulty combination light switch
An open or high resistance in the ground wire
Combination light switch OFF
Measure the voltage to ground:
There should be battery voltage.
Faulty combination light switch
A short to ground in the wire
10.
If multiple failures are found on more than one control unit, replace the body control module. If input failures are related to a particular control unit, replace the control unit.