Workshop Manuals Factory service & repair Vauxhall
Vauxhall Astra J05 · Body Systems
05 · Body & interior

Interior Backlighting Malfunction

Make
Vauxhall
Model
Astra J
Section
Lighting › Other Information › Interior Backlighting Malfunction
Body SystemsInterior Backlighting Malfunction

Interior Backlighting 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

Dimming 12 V Reference
B257B 03
B257B 03
-
-

Instrument Panel Lamps Dimmer Switch Signal
B257B 03
B257B 03
B257B 07
-

Interior Backlighting Control
B2610 02, B2625 02, B2652 02
2
1
-

Interior Backlighting Ground
-
2
-
-

1. Interior backlighting at full intensity and cannot be dimmed

2. Interior backlighting does not illuminate
 

Circuit/System Description

The body control module (BCM) supplies a voltage reference to the backlight dimmer switch, which is part of the headlamp switch. When the backlight dimmer switch is placed in a desired brightness position, reference voltage is applied through the backlight dimmer switch rheostat to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage through the backlight lamp control circuit, and the LED dimming control circuit illuminating the LEDs and the components listed below, if equipped:

•  Dome/reading lamps - front
•  Dome/reading lamps - front overhead console
•  Outside rearview mirror switch
•  Ultrasonic intrusion sensor disable switch
•  Window switch - driver
•  Window switch - passenger
•  Window switch - left rear
•  Window switch - right rear
•  Sunroof tilt switch
•  Sunroof switch
•  Passenger air bag disable indicator
•  Traction control switch
•  Door lock switch
•  Steering wheel controls switches
•  Accessory power outlet - instrument panel
•  Ignition mode switch
•  Park brake switch
•  Tour mode switch
•  Sport mode switch
•  Park assist switch
•  Headlamp switch

Reference Information


Schematic Reference

Interior Lights Dimming Schematics


Connector End View Reference

Component Connector End Views


Description and Operation

Interior Lighting Systems Description and Operation


Electrical Information Reference


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool Indicator Backlight Command parameter while operating the dimmer switch from high to low. The parameter should indicate between 4-51 percent when the backlight switch is moved up and down.
⇒ If the reading does not change, refer to Dimmer Switch Circuit Test.
2. Command the Accent Lighting 1 test with the scan tool. The appropriate backlighting items should go ON and OFF.
⇒ If the backlighting does not go ON and OFF, refer to Interior Accent Lighting Circuit Test.
3. Command the Hazard Lamps Switch Backlight test with the scan tool. The appropriate incandescent lighting items should go ON and OFF.
⇒ If the backlighting does not go ON and OFF, refer to Interior Hazard Lamps Switch Backlighting Test.
4. Command the LED Backlight Dimming test with the scan tool. The appropriate incandescent lighting items should go ON and OFF.
⇒ If the backlighting does not go ON and OFF, refer to Interior Dimming Circuit Test - LED.

Circuit/System Testing

Dimmer Switch Circuit Test

1. Ignition OFF, disconnect the harness connector at the S30 Headlamp Switch.
2. Ignition ON, test for B+ between the 12 V reference circuit terminal 1 and ground.
⇒ If less than the specified range, test the 12 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
3. Ignition ON, test for less than 0.3 V between dimming signal circuit terminal 12 and ground.
⇒ If greater than the specified range, test the dimming signal circuit terminal 12 for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
4. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the 12 V reference circuit terminal 1. The interior backlighting should now be dimmed.
⇒ If the interior backlighting is not dimmed, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
5. If all circuits test normal, test or replace the S30 Headlamp Switch.

Interior Accent Lighting Circuit Test

1. Ignition OFF, disconnect the harness connector at the appropriate inoperative backlighting component.
2. Disconnect the negative terminal of the C1 Battery.
  •  E1D Accent Lamp - Driver Door
  •  E1P Accent Lamp - Passenger Door
  •  E1V Accent Lamp - Shift Lever
3. Test for less than 5.0 Ω between the ground circuit terminal 2 wire and ground.
⇒ If greater than the specified range, test the ground circuit for an open/high resistance.
4. Reconnect the negative terminal of the C1 Battery.
5. Connect a test lamp between the dimming control circuit terminal 1 and ground.
6. Ignition ON, command the Accent Lighting 1 test ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
⇒ 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 K9 Body Control Module.
⇒ If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
7. If all circuits test normal, test or replace the appropriate component with the accent lamp.

Interior Hazard Lamps Switch Backlighting Test

1. Ignition OFF, disconnect the harness connector at the S26 Hazard Warning Switch.
2. Disconnect the negative terminal of the C1 Battery.
3. Test for less than 5.0 Ω between the ground circuit terminal 7 and ground.
⇒ If greater than the specified range, test the ground circuit for an open/high resistance.
4. Reconnect the negative terminal of the C1 Battery.
5. Connect a test lamp between the backlight control circuit terminal 8 and ground.
6. Ignition ON, command the Hazard Lamps Switch Backlight test ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
⇒ 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 K9 Body Control Module.
⇒ If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
7. If all circuits test normal, test or replace the appropriate component with the S26 Hazard Warning Switch.

Interior Dimming Circuit Test - LED

1. Ignition OFF, disconnect the harness connector at the appropriate inoperative accent light component.
2. Test for less than 5.0 Ω between the ground circuit terminal black wire and ground.
⇒ If greater than the specified range, test the ground circuit for an open/high resistance.
3. Connect a test lamp between the dimming control circuit and ground.
4. Ignition ON, command the LED Backlight Dimming test ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
⇒ 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 K9 Body Control Module.
⇒ If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
5. If all circuits test normal, test or replace the appropriate component with the inoperative accent light.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•  Control Module References for BCM, HVAC, instrument panel cluster, or radio replacement, setup, and programming

Parts & tools for this job For Vauxhall Astra

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