| Diagnosis and Testing Refer to Wiring Diagrams Section 413-00, for schematic and connector information. Principles of Operation NOTE:A new instrument cluster must be configured.
REFER to: Instrument Cluster (413-01 Instrument Cluster, Removal and Installation).
The instrument cluster and panel illumination consists of dimmable and non-dimmable illumination. The dimmable panel illumination is controlled by the panel illumination switch (part of the headlamp switch), which allows the brightness level of the backlights to be adjusted dependent on the customer preference. When the headlamp switch is in the parking lamps ON or headlamps ON position, the intensity of the backlighting can be adjusted using the panel dimmer switch. The non dimmable illumination allows for full intensity dependant on the ignition switch position. Instrument Cluster and Dimmable Backlighting The dimmable illumination utilizes light emitting diodes (LEDs) and bulb(s). The following dimmable components are backlight using LEDs only: - ashtray
- cigar lighter
- transmission control lever
- heater control panel
- audio unit
- navigation system display module
- instrument cluster
- climate control module
- hazard switch
- traction control system disable switch
- right-hand and left-hand heated front seat switch(es)
Inspection and Verification - Verify the customer concern.
- Visually inspect for obvious signs of mechanical or electrical damage.
Visual Inspection Chart | Mechanical | Electrical | - Engine/engine compartment or underbody components
- Fluid levels
- Accessory installation
| - Fuse(s)
- Loose or corroded connector(s)
- Instrument cluster
- Wiring Harness
- Circuit
- LED(s)
- Bulb(s)
| - If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step
- If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart Symptom Chart | Symptom | Possible Sources | Action | | The control illumination is inoperative | * Fuse. * Headlamp switch. * Circuit. | * | | The Instrument cluster illumination is inoperative | * Circuit(s). * Instrument cluster. | * | | The climate control illumination is inoperative | * Circuit(s). * Climate control assembly. | * | | The audio system illumination is inoperative | * Circuit(s). * Audio unit. | * | | The navigation system display module illumination (vehicles with DVD Navigation System with Touchscreen) is inoperative | * Circuit(s). * Navigation system display module. | * | | The gearshift illumination is inoperative | * Circuit(s). * Transmission Selector Lever. | * | | The cigar lighter illumination is inoperative | * Circuit(s). * Cigar lighter. | * | | The traction control switch illumination is inoperative | * Circuit(s). * Traction control switch. | * | | The hazard switch illumination is inoperative | * Circuit(s). * Hazard switch. | * | | The front seat heater switch(es) illumination is inoperative | * Circuit(s). * Front seat heater switch(es). | * | | The front window defrost switch illumination is inoperative | * Circuit(s). * Front window defrost switch. | * | | The rear window defrost switch illumination is inoperative | * Circuit(s). * Rear window defrost switch. | * | | The rear auxiliary audio control illumination is inoperative | * Circuit(s). * Rear auxiliary audio control. | * | | The instrument panel illumination does not dim | * Dimmer switch. | * INSTALL a new headlamp/dimmer switch unit. | Pinpoint Tests NOTE:Use a digital multimeter for all electrical measurements. | PINPOINT TEST A : THE CONTROL ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | A1: CHECK PARKING LAMP OPERATION | | | 1 Ignition switch in position 0. | | | 2 Place the side lamps in the ON position. | | | Do the side lamps and license plate lamps illuminate? Yes INSTALL a new headlamp switch. TEST the system for normal operation. No CHECK fuse F49 (10A). If the fuse is OK then diagnose exterior lighting.
REFER to: Headlamps (417-01, Diagnosis and Testing).
If the fuse has failed, INSTALL a new fuse. TEST the system for normal operation. If the fuse fails again, CHECK for a short to ground, REPAIR as necessary. | | PINPOINT TEST B : THE INSTRUMENT CLUSTER ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | B1: CHECK THE INSTRUMENT CLUSTER ILLUMINATION | | | 1 Place the headlamp switch in the headlamps ON position. | | | Is only the instrument cluster illumination inoperative? Yes Place the headlamp switch in the OFF position. GO to B2. No If the exterior lighting is inoperative, REFER to: Headlamps (417-01, Diagnosis and Testing). If all of the control illumination is inoperative, GO to Pinpoint Test A. | | B2: CHECK CIRCUIT 29S-GG14 (OG) FOR VOLTAGE | | | 1 Disconnect Instrument Cluster C809. | | | 2 Make sure that the illumination dimmer switch is in the full illumination position. | | | 3 Place the headlamp switch in the headlamp ON position. | | | 4 Measure the voltage between the instrument cluster C809 pin 9, circuit 29S-GG14 (OG), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit. TEST the system for normal operation. | | B3: CHECK CIRCUIT 91-GG14 (BK/OG) FOR OPEN | | | 1 Place the headlamp switch in the OFF position. | | | 2 Measure the resistance between instrument cluster C809 pin 6, circuit 91-GG14 (BK/OG), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new instrument cluster.
REFER to: Instrument Cluster (413-01 Instrument Cluster, Removal and Installation).
TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST C : THE CLIMATE CONTROL ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | C1: CHECK CIRCUIT 29S-LE10 (OG/GN) FOR VOLTAGE | | | 1 Disconnect Climate Control Assembly C378 - vehicles without electronic automatic temperature control (EATC) module or C540 - vehicles with electronic automatic temperature control (EATC) module. | | | 2 Ignition switch in position II. | | | 3 Measure the voltage between the climate control assembly C378 (vehicles without electronic automatic temperature control (EATC) module) or C540 (vehicles with electronic automatic temperature control (EATC) module) pin 3, circuit 29S-LE10 (OG/GN), harness side and ground. | | | Is the voltage greater than 10 volts? Yes Vehicles without electronic automatic temperature control (EATC) module. GO to C2. Vehicles with electronic automatic temperature control (EATC) module. GO to C3. No REPAIR the circuit. TEST the system for normal operation. | | C2: CHECK CIRCUIT 91-FA13 (BK/OG) TO GROUND | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the climate control assembly C378 pin 4, circuit 91-FA13 (BK/OG), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new climate control assembly.
REFER to: Climate Control Assembly - Vehicles With: Manual Temperature Control (412-04 Control Components, Removal and Installation).
TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | C3: CHECK CIRCUIT 91-FA94 (BK/GN) TO GROUND | | | 1 Ignition switch in position 0. | | | 2 Connect Climate Control Assembly C540. | | | 3 Disconnect Climate Control Assembly C539. | | | 4 Measure the resistance between the climate control assembly C539 pin 24, circuit 91-FA94 (BK/GN), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new climate control assembly.
REFER to: Climate Control Assembly - Vehicles With: Automatic Temperature Control (412-04 Control Components, Removal and Installation).
TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST D : THE AUDIO SYSTEM ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | D1: CHECK VOLTAGE TO THE AUDIO UNIT CIRCUIT 29S-LK34 (OG/BK) | | | 1 Ignition switch in position II. | | | 2 Disconnect Audio Unit C442. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the headlamps ON position. | | | 5 Measure the voltage between audio unit C442 pin 14, circuit 29S-LK34 (OG/BK), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit. TEST the system for normal operation. | | D2: CHECK CIRCUIT 91-MD5 (BK/BU) TO GROUND | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the audio unit C442 pin 11, circuit 91-MD5 (BK/BU), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new audio unit.
REFER to: Audio Unit - Vehicles Built Up To: 03/2007 (415-01 Audio Unit, Removal and Installation).
TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST E : THE NAVIGATION SYSTEM DISPLAY MODULE ILLUMINATION (VEHICLES WITH DVD NAVIGATION SYSTEM WITH TOUCHSCREEN) IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | E1: CHECK VOLTAGE TO THE NAVIGATION SYSTEM DISPLAY MODULE CIRCUIT 29S-LK40 (OG/BU) | | | 1 Ignition switch in position II. | | | 2 Disconnect Navigation System Display Module C487. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the headlamps ON position. | | | 5 Measure the voltage between navigation system display module C487 pin 3, circuit 29S-LK40 (OG/BU), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit. TEST the system for normal operation. | | E2: CHECK THE NAVIGATION SYSTEM DISPLAY MODULE GROUND CIRCUITS FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the navigation system display module C487 pin 11, circuit 91-GK49 (BK/GN), harness side and ground; and between the navigation system display module C487 pin 12, circuit 91-GK49A (BK/GN), harness side and ground. | | | Are the resistances less than 5 ohms? Yes INSTALL a new navigation system display module.
REFER to: Audio Unit - Vehicles Built Up To: 01/2008, Vehicles With: Digital Versatile Disc (DVD) Navigation System (415-01 Audio Unit, Removal and Installation).
TEST the system for normal operation. No REPAIR circuit 91-GK49 (BK/GN) or 91-GK49A (BK/GN). TEST the system for normal operation. | | PINPOINT TEST F : THE GEARSHIFT ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | F1: CHECK CIRCUIT 29S-PF35 (OG/BK) FOR VOLTAGE | | | 1 Disconnect Transmission Selector Lever C383. | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the headlamps ON position. | | | 5 Measure the voltage between the transmission selector lever C383 pin 2, circuit 29S-PF35 (OG/BK), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit. TEST the system for normal operation. | | F2: CHECK CIRCUIT 31-PF35 (BK) FOR VOLTAGE | | | 1 Ignition switch in position 0. | | | 2 Measure the voltage between the transmission selector lever C383 pin 4, circuit 31-PF35 (BK), harness side and ground. | | | Is the voltage greater than 10 volts? Yes INSTALL a new transmission selector lever.
REFER to: Selector Lever (307-05A, Removal and Installation).
TEST the system for normal opertion. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST G : THE CIGAR LIGHTER ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | G1: CHECK CIRCUIT 29S-LK15 (OG) FOR VOLTAGE | | | 1 Disconnect Cigar Lighter C160. | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the headlamp ON position. | | | 5 Measure the voltage between the cigar lighter C160 pin 1, circuit 29S-LK15 (OG), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit. TEST the system for normal operation. | | G2: CHECK CIRCUIT 31-HA6 (BK) FOR OPEN | | | 1 Connect Cigar Lighter C160. | | | 2 Disconnect Cigar Lighter C912. | | | 3 Measure the resistance between the cigar lighter C912 pin 1, circuit 31-HA6 (BK), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new cigar lighter. TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST H : THE TRACTION CONTROL SWITCH ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | H1: CHECK CIRCUIT 29S-LH45 (OG/WH) FOR VOLTAGE | | | 1 Disconnect Traction Control Switch C717. | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the ON position. | | | 5 Measure the voltage between the traction control switch C717 pin 3, circuit 29S-LH45 (OG/WH) harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit. TEST the system for normal operation. | | H2: CHECK CIRCUIT 91-CF54 (BK/WH) FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the traction control switch C717 pin 2, circuit 91-CF54 (BK/WH), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new traction control switch. TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST I : THE HAZARD SWITCH ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | I1: CHECK CIRCUIT 29S-LH54 (OG/GN) FOR VOLTAGE | | | 1 Disconnect Hazard Switch C455. | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the ON position. | | | 5 Measure the voltage between the hazard switch C455 pin 5, circuit 29S-LH54 (OG/GN), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit. TEST the system for normal operation. | | I2: CHECK CIRCUIT 91-LG8 (BK/OG) FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between hazard switch C455 pin 2, circuit 91-LG8 (BK/OG), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new hazard switch. TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST J : THE FRONT SEAT HEATER SWITCH ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | J1: CHECK INOPERATIVE FRONT SEAT HEATER SWITCH FOR VOLTAGE | | | 1 Disconnect Inoperative Front Seat Heater Switch - C694 (driver side) or C695 (passenger side). | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the ON position. | | | 5 Measure the voltage between the inoperative front seat heater switch: - C694 (driver side) pin 1, circuit 29S-LH29 (OG/YE), harness side and ground.
- C695 (passenger side) pin 1, circuit 29S-LH43 (OG/BU), harness side and ground.
| | | Is the voltage greater than 10 volts? Yes No REPAIR circuit 29S-LH29 (OG/YE) or circuit 29S-LH43 (OG/BU) as necessary. TEST the system for normal operation. | | J2: CHECK GROUND TO INOPERATIVE FRONT SEAT HEATER SWITCH FOR OPEN | | | 1 Measure the resistance between the inoperative front seat heater switch: - C694 (driver side) pin 2, circuit 31-LH29 (BK), harness side and ground.
- C695 (passenger side) pin 2, circuit 31-LH43 (BK), harness side and ground.
| | | Is the resistance less than 5 ohms? Yes INSTALL a new front seat heater switch. TEST the system for normal operation. No REPAIR circuit 31-LH29 (BK) or circuit 31-LH43 (BK) as necessary. TEST the system for normal operation. | | PINPOINT TEST K : THE FRONT WINDOW DEFROST SWITCH ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | K1: CHECK THE FRONT WINDOW DEFROST SWITCH FOR VOLTAGE | | | 1 Disconnect Front Window Defrost Switch C382. | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the ON position. | | | 5 Measure the voltage between the front window defrost switch C382 pin 3, circuit 29S-HB9 (OG/WH), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit 29S-HB9 (OG/WH). TEST the system for normal operation. | | K2: CHECK CIRCUIT 91-HB9 (BK/WH) FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the front window defrost switch C382 pin 2, circuit 91-HB9 (BK/WH), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new front window defrost switch. TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST L : THE REAR WINDOW DEFROST SWITCH ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | L1: CHECK THE REAR WINDOW DEFROST SWITCH FOR VOLTAGE | | | 1 Disconnect Rear Window Defrost Switch C381. | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the ON position. | | | 5 Measure the voltage between the rear window defrost switch C381 pin 3, circuit 29S-HB22 (OG/BK), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit 29S-HB22 (OG/BK). TEST the system for normal operation. | | L2: CHECK CIRCUIT 91-HB22 (BK/GN) FOR OPEN | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the rear window defrost switch C381 pin 2, circuit 91-HB9 (BK/GN), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new rear window defrost switch. TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | | PINPOINT TEST M : THE REAR AUXILAIRY AUDIO CONTROL ILLUMINATION IS INOPERATIVE | | TEST CONDITIONS | DETAILS/RESULTS/ACTIONS | | M1: CHECK THE REAR AUXILAIRY AUDIO CONTROL FOR VOLTAGE | | | 1 Disconnect Rear Auxilairy Audio Control C451. | | | 2 Ignition switch in position II. | | | 3 Make sure that the illumination dimmer switch is in the full illumination position. | | | 4 Place the headlamp switch in the ON position. | | | 5 Measure the voltage between the rear auxilairy audio control C451 pin 2, circuit 29S-MD16 (OG/GN), harness side and ground. | | | Is the voltage greater than 10 volts? Yes No REPAIR the circuit 29S-MD16 (OG/GN). TEST the system for normal operation. | | M2: CHECK CIRCUIT 91-MD16 (BK/RD) FOR GROUND | | | 1 Ignition switch in position 0. | | | 2 Measure the resistance between the rear auxiliary audio control C451 pin 3, circuit 91-MD16 (BK/RD), harness side and ground. | | | Is the resistance less than 5 ohms? Yes INSTALL a new rear auxilairy audio control.
REFER to: Rear Auxiliary Audio Controls (415-01, Removal and Installation).
TEST the system for normal operation. No REPAIR the circuit. TEST the system for normal operation. | |
