Lighting Systems Chevrolet Chevy Express H2500

Fastener Tightening Specifications

Fastener Tightening Specifications

Schematic and Routing Diagrams

For Chevy Express, see

1. G1500: «EXTERIOR LIGHTS»(ref-154376-S18171132052003080900000) , «HEADLIGHTS»(ref-154376-S04775032072003080900000) and «INTERIOR LIGHTS»(ref-154376-S40978772772003080900000) .
2. G2500: «EXTERIOR LIGHTS»(ref-154377-S16390291502003080900000) , «HEADLIGHTS»(ref-154377-S24427667802003080900000) and «INTERIOR LIGHTS»(ref-154377-S11221726112003080900000) .
3. G3500: «EXTERIOR LIGHTS»(ref-154378-S38407110152003080900000) , «HEADLIGHTS»(ref-154378-S29848789052003080900000) and «INTERIOR LIGHTS»(ref-154378-S09063696522003080900000) .
4. H1500: «EXTERIOR LIGHTS»(ref-154379-S24930472822003080900000) , «HEADLIGHTS»(ref-154379-S32048786852003080900000) and «INTERIOR LIGHTS»(ref-154379-S19551878512003080900000) .
5. H2500: «EXTERIOR LIGHTS»(ref-154380-S09458179362003080900000) , «HEADLIGHTS»(ref-154380-S10147989812003080900000) and «INTERIOR LIGHTS»(ref-154380-S42675130912003080900000) .

For Cutaway 3500, see EXTERIOR LIGHTS , HEADLIGHTS and INTERIOR LIGHTS .

For RV Cutaway 3500, see EXTERIOR LIGHTS , HEADLIGHTS and INTERIOR LIGHTS .

For GMC Savana, see

1. G1500: «EXTERIOR LIGHTS»(ref-154351-S24075084202003080900000) , «HEADLIGHTS»(ref-154351-S21401090732003080900000) and «INTERIOR LIGHTS»(ref-154351-S19352016402003080900000) .
2. G2500: «EXTERIOR LIGHTS»(ref-154352-S27437531142003080900000) , «HEADLIGHTS»(ref-154352-S01211064402003080900000) and «INTERIOR LIGHTS»(ref-154352-S17103948082003080900000) .
3. G3500: «EXTERIOR LIGHTS»(ref-154353-S23544165682003080900000) , «HEADLIGHTS»(ref-154353-S34132894372003080900000) and «INTERIOR LIGHTS»(ref-154353-S34630493562003080900000)
4. H1500: «EXTERIOR LIGHTS»(ref-154354-S10541843912003080900000) , «HEADLIGHTS»(ref-154354-S22706353502003080900000) and «INTERIOR LIGHTS»(ref-154354-S40707350812003080900000) .
5. H2500: «EXTERIOR LIGHTS»(ref-154355-S23693926962003080900000) , «HEADLIGHTS»(ref-154355-S40739833752003080900000) and «INTERIOR LIGHTS»(ref-154355-S09875396992003080900000) .

For Savana Camper Special 3500, see EXTERIOR LIGHTS , HEADLIGHTS and INTERIOR LIGHTS .

For Savana Special 3500, see EXTERIOR LIGHTS , HEADLIGHTS and INTERIOR LIGHTS .

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Begin the system diagnosis with the Diagnostic System Check - Lighting Systems . The Diagnostic System Check will provide the following information

1. The identification of the control module(s) which command the system.
2. The ability of the control module(s) to communicate through the serial data circuit.
3. The identification of any stored diagnostic trouble codes (DTCs) and their status.

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. 2. Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
2. 3. This step determines if an ignition switch power mode condition exists. The specified procedure will determine which diagnostic path is to be followed.
3. 4. This step determines if a body control module (BCM) DTC based diagnostic path or a symptom based diagnostic path are to be followed.
4. 5. The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
5. 6. This step displays stored system related DTCs to be diagnosed.

Scheme 63

Scheme 64

Scan Tool Output Controls

Body Control Module (BCM)

Scan Tool Data List

Body Control Module (BCM)

Data

Battery Voltage: The scan tool displays the battery system voltage.

Dimming Potentiometer: The scan tool displays the duty cycle of the pulse width modulated (PWM) signal distributed by the body control module (BCM) to the PWM controlled backlighting based on the position of the instrument panel (I/P) dimmer switch, thumbwheel. The scan tool displays 0 percent when the headlamp switch is in the OFF position and the daytime running lamps (DRL) are ON or the I/P dimmer switch is in the FULL DIM position. The scan tool displays 100 percent when either the headlamps or park lamps are activated and the I/P dimmer switch is in the FULL BRIGHT position.

Dimming Potentiometer R: The scan tool displays the reference voltage to the dimming potentiometer, this voltage value is 5.0 volts.

Inputs

Accessory: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the ACCESSORY, RUN or CRANK position.

Cargo Door Ajar Switch: The scan tool displays Off when the cargo door is fully closed or On when the left rear door is open or ajar.

Courtesy Lamp Switch: The scan tool displays the position of the courtesy lamp switch. The scan tool displays Active when the switch is turned ON. The BCM uses this data in controlling the operation of the courtesy lamps.

Driver Door Ajar Sw.: The scan tool displays Off when the driver door is fully closed or On when the door is open or ajar.

DRL Disable Switch: The scan tool displays the position of the DRL disable switch. The scan tool displays On when the switch is activated requesting the BCM to override the normal DRL activation inputs and deactivate the DRL.

Flash to Pass Switch: The scan tool displays the position of the flash to pass switch. The scan tool displays On when the switch is pulled to activate the high beams momentarily while the switch is held.

Headlamp Switch: The scan tool displays the position of the headlamp switch. The scan tool displays Active when the headlamp switch is in the ON position. The BCM uses this data in controlling the operation of the headlamps.

High Beam Switch: The scan tool displays the position of the high beam switch. The scan tool displays On when the switch is used to activate the high beams.

Ignition Unlock: The scan tool displays the position of the ignition switch. The scan tool displays Yes when the ignition switch is not in the locked position.

Interior Lamp Defeat Switch: The scan tool displays the position of the courtesy/dome lamp override switch. The scan tool displays On when the switch is activated requesting the BCM to override the normal interior lamp activation inputs and deactivate the interior lighting.

Key in Ignition: The scan tool displays Yes when the key has been inserted into the ignition switch. The scan tool displays No after the key has been removed.

Park Brake Switch: The scan tool displays the position of the park brake pedal. The scan tool displays Set when the park brake is engaged closing the switch. The BCM uses this data in controlling the operation of the park brake indicator, the reminder chime feature and the DRL system.

Park Lamp Switch: The scan tool displays the position of the park lamp switch. The scan tool displays Active when the park lamp switch is in the ON position. The BCM uses this data in controlling the operation of the park lamps.

Passenger/Rear Cargo Do: The scan tool displays Closed when the door is fully closed or Ajar when the door is open or ajar.

Run/Crank: The scan tool displays the position of the ignition switch. The scan tool displays On when the ignition switch is in the RUN or CRANK position.

Outputs

Backup Lamps: The scan tool displays the commanded state of the BCM which directly supplies battery positive voltage to the backup lamps. The scan tool displays On when the BCM activates the backup lamps upon receiving a backup lamp request signal from the powertrain control module (PCM).

Daytime Running Lamps: The scan tool displays the commanded state of the DRL. The scan tool displays On when the BCM signals the turn/hazard flasher module to illuminate the DRL.

Headlamps On Indicator: The scan tool displays the commanded state of the BCM which directly supplies battery positive voltage to the headlamps on indicator. The scan tool displays On when the BCM activates the headlamps on indicator upon receiving a headlamp request signal from the headlamp switch.

High Beams: The scan tool displays the commanded state of the high beam relay. The scan tool displays On when the BCM allows the high beam relay to go to ground activating the high beam headlamps.

Inadvertent Power: The scan tool displays the state of the inadvertent power battery rundown protection feature of the BCM. The scan tool displays Off when all inadvertent power circuits are functioning normally.

Low Beam Output: The scan tool displays the commanded state of the low beam relay. The scan tool displays On when the BCM allows the low beam relay to go to ground activating the high beam headlamps.

Park Lamp Relay: The scan tool displays the commanded state of the park lamp relay. The scan tool displays On when the BCM allows the park lamp relay to go to ground to activate the park lamps.

RAP Relay: The scan tool displays the commanded state of the retained accessory power (RAP) relay. The scan tool displays On when the BCM allows the relay to go to ground.

Diagnostic Trouble Code (DTC) List

Diagnostic Trouble Code (DTC) List

Circuit Description

The body control module (BCM) controls the illumination dimming of all of the control switch indicators. The BCM sets the control switch indicator illumination level according to the instrument panel (I/P) dimmer switch signal received when the component is activated and the indicator is ON. The BCM also activates the headlamp on indicator.

Voltage for the LED dimming signal, instrument panel lamps dimming control, as well as the backlight lamps control circuits is from the TBC 3 fuse 16 in the underhood fuse block directly through the BCM to these circuits.

Conditions for Running the DTC

The battery voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC

1. The headlamp on indicator control circuit is open, shorted to ground, or shorted to voltage.
2. The LED dimming signal circuit is open, shorted to ground, or shorted to voltage.
3. The backlight lamps control circuit is shorted to ground.
4. The instrument panel lamps dimming control circuit is shorted to ground.
5. There is a loss of the underhood fuse block TBC 3 battery supply voltage to the BCM for 1 second.

Diagnostic Aids

1. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .
2. A short to ground in the following circuits will cause the TBC 3 fuse to open. The backlight lamps control. The instrument panel lamps dimming control. The LED dimming signal. Battery positive voltage from the underhood fuse block TBC 3 fuse.
3. An open in the TBC 3 fuse will cause the BCM to set the following DTC: B0951 B2610 B2625

Action Taken When the DTC Sets

The headlamps on indicator will remain on with the headlamps off.

The headlamps on indicator will remain off with the headlamps on.

Conditions for Clearing the MIL/DTC

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

The numbers below refer to the step numbers on the diagnostic table.

1. 9. Determines if it is the headlamp on indicator circuit or the BCM.
2. 10. Determines if it is the headlamp on indicator circuit or the BCM.
3. 15 . After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 65

Scheme 66

The body control module (BCM) supplies battery positive voltage to the reading lamps, underhood lamp, instrument panel (I/P) compartment lamp, and both visor vanity mirror lamps. In the event that any of these lamps were to remain illuminated for more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power supply voltage circuit to prevent a total battery discharge condition.

Voltage for the inadvertent power supply voltage circuit is from the TBC 4 fuse 11 in the underhood fuse block directly through the BCM to this circuit.

The battery voltage must be between 9.0-16.0 volts.

1. The inadvertent power supply voltage circuit to the reading lamps, underhood lamp, I/P compartment lamp, and both visor vanity mirror lamps is shorted to ground for more than 1 second.
2. There is a loss of the instrument panel fuse block TBC 4 battery supply voltage to the BCM for 1 second while one or more of the lamps in the inadvertent power circuit has been activated.

The reading lamps, underhood lamp, I/P compartment lamp, and both visor vanity mirror lamps will not operate.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .
2. A short to ground in the inadvertent power supply voltage circuit or the battery positive voltage circuit will cause the TBC 4 fuse to open.

The numbers below Refer to the step numbers on the diagnostic table.

1. 3. This step test determines if the problem exists in the wiring or the BCM.
2. 5. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 67

When the body control module (BCM) senses a request for low beam headlamp illumination, the BCM sends a ground signal to the low beam headlamp relay through the headlamp low beam relay control circuit. The headlamp low beam relay will apply voltage to illuminate the headlamps.

The battery voltage must be between 9.0-16.0 volts.

1. When the low beam headlamp relay control circuit is open or shorted to ground.
2. When the BCM receives a low beam headlamp ON command and the low beam headlamp relay control circuit is shorted to voltage.
3. When the low beam relay coil side is open or the battery positive voltage to the low beam relay is open.

The low beam headlamps will not operate or will remain always on.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTC(s) can be cleared using a scan tool.

The numbers below Refer to the step numbers on the diagnostic table.

1. 3. Tests for voltage at the voltage supply side of the headlamp low beam relay.
2. 4. Verifies that the body control module (BCM) is providing ground to the headlamp low beam relay.
3. 5. Tests if ground is constantly being applied to the headlamp low beam relay.
4. 6. Tests if there is opposing voltage present or an open headlamp low beam relay control circuit.
5. 12. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 68

Scheme 69

When the body control module (BCM) receives a ground signal from the multifunction high beam or flash to pass (FTP) switch commanding to illuminate the high beam headlamps, the BCM will energize the high beam relay by grounding the high beam relay control circuit.

The battery voltage must be between 9.0-16.0 volts.

1. When the high beam headlamp relay control circuit is open or shorted to ground.
2. When the BCM receives a high beam headlamp ON command and the high beam headlamp relay control circuit is shorted to voltage.
3. When the high beam relay coil side is open or the battery positive voltage to the high beam relay is open.

The high beam headlamps will not operate or will remain always on.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

The numbers below Refer to the step numbers on the diagnostic table.

1. 2. Listen for an audible click when the high beam relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
2. 3. Tests for voltage at the coil side of the high beam relay.
3. 4. Verifies that the body control module (BCM) is providing ground to the high beam relay.
4. 5. Tests if ground is constantly being applied to the high beam relay.
5. 6. Tests if there is opposing voltage present or an open high beam relay control circuit.
6. 12. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 70

Scheme 71

When the body control module (BCM) receives a ground signal from the headlamp switch commanding to illuminate the park lamps, the BCM will energize the park lamp relay by grounding the park lamp relay control circuit.

The battery voltage must be between 9.0-16.0 volts.

1. When the park lamp relay control circuit is open or shorted to ground.
2. When the BCM receives a park lamp ON command and the park lamp relay control circuit is shorted to voltage.
3. When the park lamp relay coil side is open or the battery positive voltage to the low beam relay is open.

The park lamps will not operate or will remain always on.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTC(s) can be cleared using a scan tool.

The numbers below Refer to the step numbers on the diagnostic table.

1. 2. Listen for an audible click when the park lamp relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
2. 3. Tests for voltage at the coil side of the park lamp relay.
3. 4. Verifies that the body control module (BCM) is providing ground to the park lamp relay.
4. 5. Tests if ground is constantly being applied to the park lamp relay.
5. 6. Tests if there is opposing voltage present or an open park lamp relay control circuit.
6. 12. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 72

Scheme 73

The body control module (BCM) signals the turn/hazard flasher module to illuminate the daytime running lamps (DRL) by grounding the DRL low control circuit. The DRL operates when the ignition switch is in the RUN position and the gear selector is not in the park position.

The battery voltage must be between 9.0-16.0 volts.

1. When the BCM sends a DRL OFF command and the DRL low control circuit is shorted to ground.
2. When the BCM sends a DRL ON command and the DRL low control circuit is shorted to voltage or open.
3. When the Flasher fuse 15 in the underhood fuse block is open.
4. When the following circuits are shorted to ground: Left rear stop/turn lamp supply voltage Right rear stop/turn lamp supply voltage Left DRL/turn supply voltage Right DRL/turn supply voltage Left turn signal indicator lamp supply voltage Right turn signal indicator lamp supply voltage Battery supply voltage from the underhood fuse block Flasher fuse
5. The instrument panel lamps dimming control circuit is shorted to ground.

The DRL will not operate or will remain always on.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .
2. A short to ground in the following circuits will cause the Flasher fuse to open. Left rear stop/turn lamp supply voltage Right rear stop/turn lamp supply voltage Left DRL/turn supply voltage Right DRL/turn supply voltage Left turn signal indicator lamp supply voltage Right turn signal indicator lamp supply voltage Battery supply voltage from the underhood fuse block Flasher fuse
3. An open in the Flasher fuse will cause the DRL, turn signals and the hazard flashers to be inoperative.

The numbers below Refer to the step numbers on the diagnostic table.

1. 2. This step test determines if the problem exists in the DRL control/BCM or other circuitry.
2. 3. This step test determines if the problem exists in the wiring or the BCM.
3. 7. This step test determines if the problem exists in the wiring or the BCM.
4. 9. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 74

The body control module (BCM) receives a variable voltage signal from the instrument panel (I/P) dimmer switch requesting to illuminate the instrument panel controls illumination lamps to a desired intensity. When this occurs, the BCM directly sends a variable voltage based on the I/P dimmer switch position on the backlight lamps control circuit, instrument panel lamps dimming control circuit, and the LED dimming signal circuit.

Voltage for the backlight lamps control circuit, instrument panel lamps dimming control circuit, and the LED dimming signal circuits is from the TBC 3 fuse 16 in the underhood fuse block directly through the BCM to these circuits.

The battery voltage must be between 9.0-16.0 volts.

1. The backlight lamps control circuit is open, shorted to ground, or shorted to voltage.
2. The instrument panel lamps dimming control circuit is open, shorted to ground, or shorted to voltage.
3. The LED dimming signal circuit is shorted to ground.
4. There is a loss of the underhood fuse block TBC 3 battery supply voltage to the BCM for 1 second.

The instrument panel illumination lamps and the controls illumination lamps will not operate or are always ON.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .
2. A short to ground in the following circuits will cause the TBC 3 fuse to open. The backlight lamps control. The instrument panel lamps dimming control. The LED dimming signal. Battery positive voltage from the underhood fuse block TBC 3 fuse.
3. An open in the TBC 3 fuse will cause the BCM to set the following DTC: B0951 B2610 B2625

The numbers below Refer to the step numbers on the diagnostic table.

1. 5. This step test determines if the problem exists in the headlamp switch or the BCM.
2. 10. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 75

The body control module (BCM) receives a ground signal from the door jamb, or courtesy lamp switch requesting courtesy/dome lamp illumination. When this occurs, the BCM directly sends a voltage through the courtesy lamp supply voltage circuit illuminating the courtesy/dome lamps.

Voltage for the courtesy lamp supply voltage circuit as well as the backup lamp supply voltage circuit is from the body fuse block TBC 2 fuse directly through the BCM to these circuits.

The battery voltage must be between 9.0-16.0 volts.

1. When the BCM receives a courtesy lamp illumination request signal and the courtesy lamp supply voltage circuit is shorted to ground.
2. When the BCM is not receiving a courtesy lamp illumination request signal and the courtesy lamp supply voltage circuit is open before the first connection after the BCM or shorted to voltage.
3. There is a loss of the body fuse block TBC 2 battery supply voltage to the BCM for 1 second.

The courtesy dome lamps will not operate or are always ON.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .
2. An open circuit up to the first splice only in the courtesy lamp supply voltage circuit from the BCM, will set the DTC.
3. A short to ground in the following circuits will cause the TBC 2 fuse to open. Courtesy lamp supply voltage. Backup lamp supply voltage. Battery positive voltage from the body fuse block TBC 2 fuse.

The numbers below Refer to the step numbers on the diagnostic table.

1. 2. This step test determines if the problem is a short to ground in the wiring.
2. 3. This step test determines if the problem exists in the wiring or the BCM.
3. 4. This step test determines if the problem exists in the wiring or the BCM.
4. 6. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 76

The body control module (BCM) receives a ground signal from the door jamb or courtesy lamp switches requesting courtesy/dome lamp illumination. When this occurs, the BCM sends a voltage through the courtesy lamp high control circuit to the courtesy lamp relay, illuminating the courtesy/dome lamps.

Voltage for the courtesy lamp high control circuit as well as the backup lamp supply voltage circuit is from the body fuse block TBC 2 fuse directly through the BCM to these circuits.

The battery voltage must be between 9.0-16.0 volts.

1. When the BCM receives a courtesy lamp illumination request signal and the courtesy lamp high control circuit is shorted to ground.
2. When the BCM is not receiving a courtesy lamp illumination request signal and the courtesy lamp high control circuit is open or shorted to voltage.
3. When the courtesy lamp relay coil side is open.
4. There is a loss of the body fuse block TBC 2 battery supply voltage to the BCM for 1 second.

The courtesy dome lamps will not operate or are always ON.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .
2. A short to ground in the following circuits will cause the TBC 2 fuse to open. Courtesy lamp high control. Backup lamp supply voltage. Battery positive voltage from the body fuse block TBC 2 fuse.

The numbers below Refer to the step numbers on the diagnostic table.

1. 5. This step tests for an open coil in the courtesy lamp relay.
2. 8. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 77

The body control module (BCM) directly sends a 5 volt reference voltage to the instrument panel (I/P) dimmer switch which is then adjusted based on the I/P dimmer switch position and returned as a low reference and a signal to the BCM. The BCM uses this signal to directly control the desired level of instrument panel illumination lamp intensity.

The battery voltage must be between 9.0-16.0 volts.

1. When the BCM monitors a 5 volt reference circuit voltage of less than 4.5 volts.
2. When the BCM monitors a 5 volt reference circuit voltage of greater than 5.5 volts.
3. When the BCM monitors a signal voltage of equal or greater than 4.86 volts for more than 1 second.

The instrument panel illumination lamp dimming will not operate.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

The numbers below Refer to the step numbers on the diagnostic table.

1. 3. Tests for the proper operation of the circuit in the low voltage range.
2. 4. Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
3. 5. Tests for a short to voltage in the 5 volt reference circuit.
4. 6. Tests for a high resistance or an open in the low reference circuit.

Scheme 78

Scheme 79

The body control module (BCM) receives a variable voltage signal from the instrument panel (I/P) dimmer switch requesting to illuminate the dimming lamps to a desired intensity. When this occurs, the BCM directly sends a pulse width modulated (PWM) voltage based on the I/P dimmer switch position on the LED dimming signal circuit, instrument panel lamps dimming control circuit, and the backlight lamps control circuit.

Voltage for the LED dimming signal circuit, instrument panel lamps dimming control circuit, and the backlight lamps control circuit is from the TBC 3 fuse 16 in the underhood fuse block directly through the BCM to these circuits.

The battery voltage must be between 9.0-16.0 volts.

1. The backlight lamps control circuit is shorted to ground.
2. The instrument panel lamps dimming control circuit is shorted to ground.
3. The LED dimming signal circuit is shorted to ground.
4. There is a loss of the underhood fuse block TBC 3 battery supply voltage to the BCM for 1 second.

The dimming lamps will not operate.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTC(s) can be cleared using a scan tool.

1. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .
2. A short to ground in the following circuits will cause the TBC 3 fuse to open. The backlight lamps control. The instrument panel lamps dimming control. The LED dimming signal. Battery positive voltage from the underhood fuse block TBC 3 fuse.
3. An open in the TBC 3 fuse will cause the BCM to set the following DTC: B0951 B2610 B2625

The number below refers to the step number on the diagnostic table.

1. 4. After replacement of the BCM you must calibrate the new module for proper operation.

Scheme 80

The body control module (BCM) monitors the courtesy lamp switch signal circuit in order to determine when the courtesy/dome lamps should be illuminated. When the BCM senses that the courtesy lamp switch signal circuit is grounded when the switch is activated, the BCM will illuminate the courtesy/dome lamps.

1. The BCM instrument panel dimmer switch reference voltage must be between 4.5-5.5 volts.
2. The battery voltage must be between 9.0-16.0 volts.

1. When the instrument panel dimmer switch signal is greater than 1.0 volt.
2. When the BCM receives a courtesy lamp ON request signal from the courtesy lamp switch.

The courtesy/dome lamps will not operate.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

1. Test the courtesy lamp switch for sticking in the ON position.
2. Perform a visual inspection for loose or poor connections at all related components. Refer to «TESTING FOR INTERMITTENT AND POOR CONNECTIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__testing-for-intermittent-and-poor-connections) .

Scheme 81

The body control module (BCM) monitors the park lamp switch on signal circuit and the headlamp switch headlamps on signal circuit in order to determine when the park lamps and headlamps should be illuminated. When the headlamp switch is turned to PARK, the BCM senses that the park lamp switch signal on circuit is grounded and the headlamps switch headlamps ON signal circuit is open. The BCM will then energize the park lamp relay illuminating the park lamps. When the headlamp switch is turned to HEAD, the BCM senses that the park lamp switch on signal circuit and the headlamp switch headlamps ON signal circuit are grounded. The BCM will then energize the park lamp relay and headlamp low beam relay or high beam relay illuminating the park lamps and headlamps.

The battery voltage must be between 9.0-16.0 volts.

When the headlamp switch park lamps on signal circuit is open or has a high resistance.

When the headlamp switch headlamps on signal circuit is shorted to ground.

The park lamps will not operate or the headlamps will illuminate without the park lamps.

1. This DTC will clear on current status after the condition for setting the fault is corrected.
2. A history DTC will clear after 100 consecutive ignition cycles without a fault present.
3. History and current DTCs can be cleared using a scan tool.

Scheme 82

Scheme 83

1. Perform the «Diagnostic System Check - Lighting Systems»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems) on before using the Symptom Tables in order to verify that all of the following are true: There are no DTCs set. The control modules can communicate via the serial data link.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to the following: «Exterior Lighting Systems Description and Operation»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems) «Interior Lighting Systems Description and Operation»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the Lighting System. Refer to «CHECKING AFTERMARKET ACCESSORIES»(/chevrolet/chevy-express-h2500/2003-2003/remont/electrical-component-locations/#wiring-systems-general-information__checking-aftermarket-accessories) .
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. «Backup Lamps Always On»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
2. «Backup Lamps Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
3. «Courtesy Lamps Always On»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
4. «Courtesy Lamps Inoperative (Lamps)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
5. «Courtesy Lamps Inoperative (Defeat Switch)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
6. «Daytime Running Lamps (DRL) Inoperative (Lamps)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems) or «Daytime Running Lamps (DRL) Inoperative (Defeat Switch)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
7. «Dome Lamps Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
8. «Hazard Lamps Always On»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
9. «Hazard Lamps Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
10. «Headlamps Always On - Low or High Beam»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
11. «Headlamps Inoperative - High Beams»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
12. «Headlamps Inoperative - Low Beams»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
13. «Headlamps Inoperative - Low and High Beams»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
14. «Headlamps Inoperative - Flash to Pass»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
15. «High Beam Indicator Always On»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
16. «High Beam Indicator Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
17. «Interior Backlighting Does Not Dim»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
18. «Interior Backlighting Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
19. «Park, License, and Tail Lamps Always On»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
20. «Park, License, and Tail Lamps Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
21. «Reading Lamp(s) Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
22. «Stop Lamps Always On»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
23. «Stop Lamps Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
24. «Turn Signal Lamps and/or Indicators Always On or Flashing»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
25. «Turn Signal Lamps and/or Indicators Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
26. «Underhood Lamp Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)
27. «Vanity Mirror Lamp(s) Inoperative»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-lights/#lighting-systems)

Scheme 84

Scheme 85

Scheme 86

Scheme 87

Scheme 88

Scheme 89

Scheme 90

Scheme 91

Scheme 92

Scheme 93

Scheme 94

Scheme 95

Scheme 96

Scheme 97

Scheme 98

Scheme 99

Scheme 100

Scheme 101

Scheme 102

Scheme 103

Scheme 104

Scheme 105

Scheme 106

Scheme 107

Scheme 108

Scheme 109

Scheme 110

Scheme 111

Scheme 112

Scheme 113

Scheme 114

Scheme 115

Scheme 116

Scheme 117

Scheme 118

Scheme 119

Scheme 120

Scheme 121

Scheme 122

Scheme 123

Scheme 124

Scheme 125

Scheme 126

Scheme 127

Scheme 128

Scheme 129

Scheme 130

Removal Procedure

Scheme 131

1. Disconnect the battery negative cable. Refer to «BATTERY NEGATIVE CABLE DISCONNECT/CONNECT PROCEDURE»(/chevrolet/chevy-express-h2500/2003-2003/remont/body-electrical/#battery) .
2. Disconnect the electrical connector from the stop lamp switch.
3. Remove the retainer from the brake pedal pin.
4. Remove the stop lamp switch and the pushrod to the power brake booster from the brake pedal pin.
5. Unsnap the stop lamp switch from the power brake booster pushrod.

Scheme 132

1. Snap the stop lamp switch onto the pushrod to the power brake booster.
2. Install the stop lamp switch with the pushrod on the brake pedal pin.
3. Connect the electrical connector to the stop lamp switch.
4. Connect the battery negative cable. Refer to «BATTERY NEGATIVE CABLE DISCONNECT/CONNECT PROCEDURE»(/chevrolet/chevy-express-h2500/2003-2003/remont/body-electrical/#battery) .

Scheme 133

1. Remove the instrument panel cluster trim plate. Refer to «TRIM PLATE BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER»(/chevrolet/chevy-express-h2500/2003-2003/remont/gauges-instrument-panels/#instrument-panel-gages-and-console__trim-plate-bezel-replacement-instrument) .
2. Disconnect the electrical connector from the headlamp switch.
3. Remove the headlamp switch from the instrument panel cluster trim plate by releasing the retainers on the instrument panel cluster trim plate from the headlamp switch.
4. Remove the headlamp switch from the vehicle.

Scheme 134

1. Install the headlamp switch to the vehicle.
2. Connect the headlamp switch to the instrument panel cluster trim plate by pushing on the switch in order to engage the retainers on the instrument panel cluster trim plate.
3. Connect the electrical connector to the headlamp switch.
4. Install the instrument panel cluster trim plate. Refer to «TRIM PLATE BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER»(/chevrolet/chevy-express-h2500/2003-2003/remont/gauges-instrument-panels/#instrument-panel-gages-and-console__trim-plate-bezel-replacement-instrument) .

Important: Avoid excessive force when prying the bezel from the instrument panel extension.

Scheme 135

Scheme 136

1. Pry the bezel from the instrument panel extension using a flat-bladed tool.
2. Remove the electrical connector from the rear fog lamp switch.
3. Press the tabs on the rear fog lamp switch in order to disengage the tabs from the bezel.
4. Remove the rear fog lamp switch from the vehicle.

Scheme 137

Scheme 138

1. Install the following components to the instrument panel extension: The rear fog lamp switch The bezel
2. Apply pressure to the rear fog lamp switch in order to engage the tabs on the switch to the bezel.
3. Install the rear fog lamp switch.
4. Install the electrical connector to the rear fog lamp switch.
5. Install the bezel to the lower panel extension.

Scheme 139

1. Remove the left knee bolster bracket. Refer to «KNEE BOLSTER BRACKET REPLACEMENT - LEFT»(/chevrolet/chevy-express-h2500/2003-2003/remont/gauges-instrument-panels/#instrument-panel-gages-and-console__knee-bolster-bracket-replacement-left) .
2. Remove the turn / hazard flasher (2) from the Instrument Panel (I/P) Support.
3. Disconnect the electrical connector (1).
4. Remove the turn / hazard flasher (2).

Scheme 140

1. Connect the electrical connector (1) to the turn / hazard Flasher (2).
2. Install the turn / hazard flasher (2) to the Instrument Panel (I/P) Support.
3. Install the left knee bolster bracket. Refer to «KNEE BOLSTER BRACKET REPLACEMENT - LEFT»(/chevrolet/chevy-express-h2500/2003-2003/remont/gauges-instrument-panels/#instrument-panel-gages-and-console__knee-bolster-bracket-replacement-left) .

Scheme 141

1. Gently pry out the lens (2) of the vanity mirror assembly (4) with a suitable flat-bladed tool.
2. Remove the bulb (3) from the socket.

Scheme 142

1. Install the bulb (3) into the bulb socket.
2. Install the lens (2) to the vanity mirror assembly (4) by pressing it into place.

Scheme 143

Scheme 144

Scheme 145

1. Using a flat bladed tool, pry the dome lamp lens open.
2. Remove the dome lamp lens (2) completely from the dome lamp housing.
3. Partially remove the dome lamp housing (1) from the headliner.
4. Disconnect the electrical connector (2) from the dome lamp housing.

Scheme 146

Scheme 147

1. Partially install the dome lamp housing (1) to the headliner.
2. Connect the dome lamp electrical connector (2).
3. Install the dome lamp lens (2) to the dome lamp housing.
4. Snap the dome lamp lens (2) into the dome lamp housing.

Scheme 148

Scheme 149

1. Using a flat bladed tool, pry the dome lamp lens open.
2. Remove the dome lamp bulbs (1) from the dome lamp housing.

Scheme 150

1. Install the dome lamp bulbs (1).
2. Snap the dome lamp lens (2) into the housing.

Scheme 151

1. Disconnect the electrical connector (3) from the underhood lamp (1).
2. Release the retaining clip (2).
3. Remove the underhood lamp (1).

Scheme 152

1. Install the underhood lamp (1).
2. Install the electrical connector cord into the retaining clip (2) and close to retain the cord.
3. Connect the electrical connector (3) to the underhood lamp (1).

Scheme 153

1. Turn OFF the headlamp switch.
2. Remove the retaining ring screws from the headlamp. Do not move the adjustment screws.
3. Remove the retaining ring from the headlamp.
4. Remove the headlamp from the housing.
5. Disconnect the electrical connector from the headlamp.

Scheme 154

1. Connect the electrical connector to the headlamp.
2. Install the headlamp to the housing.
3. Install the retaining ring to the headlamp.
4. Install the screws to the retaining ring.

1. Turn OFF the headlamp switch.
2. Disconnect the electrical connector from the headlamp bulb. WARNING: Halogen bulbs contain gas under pressure. Handling a bulb improperly could cause it to shatter into flying glass fragments. To help avoid personal injury: Turn off the lamp switch and allow the bulb to cool before changing the bulb. Leave the lamp switch OFF until the bulb change is complete. Always wear eye protection when changing a halogen bulb. Handle the bulb only by its base. Avoid touching the glass. Keep dirt and moisture off the bulb. Properly dispose of the used bulb. Keep halogen bulbs out of the reach of children.
3. Rotate the bulb counterclockwise in order to disengage the bulb from the headlamp.
4. Remove the bulb from the headlamp.

Scheme 155

1. Install the bulb to the headlamp.
2. Rotate the bulb clockwise in order to engage the bulb in the headlamp.
3. Connect the electrical connector to the headlamp bulb.

Scheme 156

1. Turn OFF the headlamp switch.
2. Remove the radiator grille. Refer to «GRILLE REPLACEMENT (UPLEVEL)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exteriorinterior-trim/#exterior-trim) or «GRILLE REPLACEMENT (BASE)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exteriorinterior-trim/#exterior-trim) .
3. Remove the bolts (5) that retain the composite headlamp to the radiator support. Do not move the adjustment screws. WARNING: Refer to «HALOGEN BULB CAUTION»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__halogen-bulb-caution) .
4. Disconnect the electrical connector (1) from the headlamp assembly.
5. Remove the composite headlamp (4) from the vehicle.

Installation Procedure

Scheme 157

1. Connect the electrical connector (1) to the headlamp assembly.
2. Install the composite headlamp (4) to the vehicle. CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
3. Install the composite headlamp retaining bolts (5) to the radiator support. Tighten Tighten the bolts to 11 N.m (97 lb in).
4. Install the radiator grille. Refer to «GRILLE REPLACEMENT (UPLEVEL)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exteriorinterior-trim/#exterior-trim) or «GRILLE REPLACEMENT (BASE)»(/chevrolet/chevy-express-h2500/2003-2003/remont/exteriorinterior-trim/#exterior-trim) .

Headlamp Aiming

The screen method is preferred for aiming headlamps. If the headlamp is equipped with aiming pads, headlamp aiming may be performed using the alternate procedure.

Headlamp aiming is done with the vehicle's low beam lamps. The high beam lamps will be correctly aimed if the low beam lamps are aimed properly. If the high beam needs adjustment, follow the screen method using the high beam bulb as the reference for measurements.

Screen Method for Headlamp Aiming (Visual Aim)

Important: Some state and local laws specify requirements for headlamp aim. All of these laws must be complied with when performing any headlamp aiming operations.

Headlamp aim should be checked

1. When a new headlamp capsule is installed
2. If service or repairs to the front end area have (or may have) disturbed the headlamps or their mounting
3. The area will consist of a level surface large enough to allow for a vehicle and an additional 7.62 m (25 feet) measured from face of lamps to the front of the aiming screen.
4. The screen will be 1.52 m (5 ft) high x 3.66 m (12 ft) wide with a matte white surface well shaded from extraneous light, and properly adjusted to the floor on which the vehicle stands. Provisions may be made for moving the screen so it can be aligned parallel with the vehicle.
5. The screen shall be provided with a fixed vertical centerline, two laterally adjustable vertical tapes, and one vertically adjustable horizontal tape.
6. If a regular commercial aiming screen is not available, the screen may consist of a vertical wall having a clear uninterrupted area approximately 1.83 m (6 ft) high and 3.66 m (12 ft) wide. The surface should be finished with a washable non-gloss white paint.
7. After the aiming screen has been set up in its permanent location, it is necessary to paint a reference line on the floor directly under the lens of the lamps to indicate the proper location of the headlamps when they are being aimed: Distance between headlamps (1) Center line of screen (2) Adjustable vertical pointer (3) Adjustable horizontal tape (4) Diagram of light screen (5) Vertical center line ahead of right headlamp pointer position (6) 7.62 m (25 ft) (7) Car axis (8) Adjustable vertical pointer Horizontal center line of lamps Vertical center line ahead of left headlamp

Prior to aiming the headlamps, the following steps must be taken

1. Remove any snow, ice or mud from the vehicle.
2. The vehicle must have a full tank of gas.
3. Stop all other work on the vehicle.
4. If any service has been performed on the vehicle, make sure that all of the components are back in their original place.
5. The vehicle must be on a level surface.
6. The vehicle left tires must be aligned with the reference line extending from the screen with the headlamps aligned with the reference line.
7. Do not load any cargo in the vehicle.
8. The vehicle must contain one person or 72.56 kg (160 lb) on the driver's seat.
9. Inflate the tires to the proper pressure.
10. Simulate the vehicle loads if the intended use of the vehicle is for hauling heavy loads or towing a trailer.
11. Rock the vehicle in order to stabilize the suspension.
12. Turn on the headlamps to low beam and observe the left and the top edges of the high intensity zone on the screen. The edges of the high intensity zone should fall within the specifications.

Scheme 158

1. Open the hood.
2. Measure from the floor to the center of the headlamp bulb. (Some headlamps have an aim dot marked on the headlamp lens).
3. At the screen, measure from the floor and place the horizontal tape at the measured distance.
4. Measure from the reference line on the floor to the left headlamp bulb centerline.
5. At the screen, measure from the reference line and place the vertical tape at the measured distance.
6. Measure from the reference line on the floor to the right headlamp bulb centerline.
7. At the screen, measure from the reference line and place the vertical tape at the measured distance. Important: Do not cover the headlamp, this may cause excessive heat build up.
8. Turn on the low beam headlamps and block the light from projecting onto the screen from the passenger side headlamp.
9. Adjust the vertical aim of the headlamps to the specifications required by the state and the local authorities, or as shown in step number 8.
10. Rotate the headlamp adjuster (1) to change the vertical aim of the headlamp.
11. Repeat the aiming procedure for the passenger side headlamp while blocking the light from projecting onto the screen from the driver side headlamp.
12. Close the hood.
13. This illustration represents the visual optics left (VOL) pattern.
14. This illustration represents the visual optics right (VOR) pattern.
15. This illustration represents all headlamps, except the VOL and VOR.
16. This illustration represents the high beam pattern for all headlamps, including VOL and VOR.

Tool Required

Composite Headlight Aimer Adapter

Instructions for use accompany the tool.

This procedure may only be used on headlamps equipped with aiming pads. Adjustment settings are embossed on the headlamp lens. They are typically located near the aiming pads. In some cases, the adjustment settings are located in other areas of the lens. They will be represented by a number followed by the letter V or the letter H.

1. Remove any snow, ice or mud from the vehicle.
2. The vehicle should be fully assembled and all other work stopped while the headlamp aiming is being done.
3. The vehicle should contain cargo or be loaded to represent normal vehicle use.
4. Tires should be properly inflated.
5. Rock the vehicle to stabilize the suspension.
6. Using, adjust the headlamps to the specifications required by state and local authorities.

Scheme 159

Scheme 160

1. Disconnect the electrical connector from the lamp assembly.
2. Remove the nut retaining the lamp assembly to the bracket.
3. Remove the lamp assembly from the bumper.

Scheme 161

Scheme 162

1. Install the lamp assembly to the bumper. CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
2. Install the nut to retain the lamp assembly to the bracket. Tighten Tighten the nut to 2 N.m (18 in lb).
3. Install the electrical connector to the lamp assembly.

Scheme 163

1. Remove the screws retaining the lens to the lamp.
2. Remove the lens from the lamp.
3. Gently push in on the bulb and turn the bulb 1/4 turn counterclockwise.
4. Remove the bulb from the socket.

Scheme 164

1. Install the bulb to the socket.
2. Gently push in on the bulb and turn the bulb 1/4 turn clockwise.
3. Install the lens to the lamp assembly. CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the screws to retain the lens to the lamp assembly. Tighten Tighten the screws to 1.5 N.m (13 lb in).

Scheme 165

1. Remove the screws holding the retaining ring to the headlamp housing assembly.
2. Remove the retaining ring from the position lamp.
3. Remove the headlamp capsule (1) from the position lamp.
4. Remove the bulb (4) and socket from the rubber grommet in the lamp capsule.
5. Push in on the side of the bulb (4) and turn the bulb 1/4 turn counterclockwise.
6. Remove the bulb (4) from the socket.

Scheme 166

1. Install the bulb (4) to the socket.
2. Push in on the bulb (4) and turn 1/4 turn clockwise.
3. Install the bulb (4) and socket into the rubber grommet in the headlamp capsule (1).
4. Install the headlamp capsule (1) to the headlamp housing.
5. Install the retaining ring to the headlamp housing assembly. CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
6. Install the screws to the retaining ring to the headlamp housing assembly. Tighten Tighten the screws to 1.5 N.m (13 lb in).

Scheme 167

1. Push the light assembly (2) towards the front of the vehicle while gently prying the rear edge of the light assembly away from the fender with a small flat-bladed tool in order to remove the light assembly.
2. Remove the bulb and socket from the light assembly (3) by turning the socket 1/4 turn counterclockwise.
3. Remove the bulb (1) from the socket.

Scheme 168

1. Install the bulb (1) into the socket.
2. Turn the socket (3) 1/4 turn clockwise in order to install the socket into the light assembly.
3. Hook the front tab on the lens into the fender and press the light assembly (2) retaining clip into the fender until fully seated.

Scheme 169

1. Remove the screw (4) that retains the front side marker lamp to the radiator grille.
2. Lift the side marker lamp (3) up and out in order to disengage the tab.
3. Disconnect the bulb socket (1) from the side marker lamp.
4. Remove the bulb (1) from the socket.

Scheme 170

1. Connect the bulb (1) into the socket.
2. Connect the bulb socket (1) into the side marker lamp.
3. Install the side marker lamp (3) to the radiator grille (5). CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the side marker lamp retaining screw (4). Tighten Tighten the screws to 1.5 N.m (13 lb in).

Scheme 171

1. Remove the screw (4) that retains the side marker or the reflector to the grille.
2. Remove the side marker lamp (3) or the reflector (5) from the grille.
3. Disconnect the bulb socket (2) from the side marker lamp.
4. Remove the bulb (2) from the socket by turning the bulb in a counter clockwise direction.

Scheme 172

1. Install the bulb (2) into the socket by turning the bulb in a clockwise direction.
2. Connect the bulb socket (2) into the side marker lamp.
3. Install the side marker lamp (3) or the reflector (5) to the radiator grille (1). CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the side marker lamp or reflector retaining screw (4) to the grille. Tighten Tighten the screws to 1.5 N.m (13 lb in).

Scheme 173

1. Remove the screws (4) from the park/turn signal lamp to the grille.
2. Remove the park/turn signal lamp (3) from the grille.
3. Disconnect the bulb socket(s) (1) from the park/turn signal lamp by turning the bulb sockets in a counterclockwise direction.
4. Remove the bulb(s) (1) from the socket.

Scheme 174

1. Install the bulb(s) (1) into the socket by turning the bulb sockets in a clockwise direction.
2. Connect the bulb socket(s) (1) into the park/turn ' signal lamp.
3. Install the park/turn signal lamp (3) to the grille (5). CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the park/turn signal lamp retaining screws (4) to the grille. Tighten Tighten the screws to 1.5 N.m (13 lb in).

Scheme 175

1. Remove the screws (3) from the park/turn signal lamp to the grille.
2. Remove the park/turn signal lamp (2) from the grille.
3. Disconnect the bulb socket (1) from the park/turn signal lamp by turning the bulb sockets in a counterclockwise direction.
4. Remove the bulb (1) from the socket.

Scheme 176

1. Install the bulb (1) into the socket by turning the bulb sockets in a clockwise direction.
2. Connect the bulb socket (1) into the park/turn signal lamp.
3. Install the park/turn signal lamp (2) to the grille (5). CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the park/turn signal lamp retaining screws (3) to the grille. Tighten Tighten the screws to 1.5 N.m (13 lb in).

Scheme 177

1. Remove the screws (3) that retain the center high mounted stop lamp lens.
2. Remove the center high mounted stop lamp lens (2).
3. Disconnect the bulb socket (1) from the center high mounted stop lamp.
4. Remove the bulb (1) from the socket.

Scheme 178

1. Install the bulb (1) into the socket.
2. Connect the bulb socket (1) into the center high mounted stop lamp lens.
3. Install the center high mounted stop lamp lens (2). CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the center high mounted stop lamp lens retaining screws (3). Tighten Tighten the center high mounted stop lamp lens screws to 1.5 N.m (13 lb in).

Scheme 179

1. Disconnect the electrical connector.
2. Using a plastic flat bladed tool, release the double sided tape that retains the light assembly to the vehicle.

Scheme 180

1. Install the light assembly into the vehicle with double sided tape. Important: In order to insure a good replacement of new adhesive or of old adhesive, verify that the surface meets the following conditions: The temperature of the surface is approximately 24-41 °C (80-105°F). The surface is clean. The surface is free of wax or of oily film.
2. Connect the electrical connector.

Scheme 181

Scheme 182

1. Disconnect the electrical connector from the lamp assembly.
2. Remove the nut retaining the lamp assembly to the bracket.
3. Remove the lamp assembly from the bumper.

Scheme 183

Scheme 184

1. Install the lamp assembly to the bumper. CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
2. Install the nut to the lamp. Tighten Tighten the nut to 2 N.m (18 in lb).
3. Connect the electrical connector to the lamp assembly.

Scheme 185

1. Remove the screws the lens to the lamp assembly.
2. Remove the lens from the lamp assembly.
3. Gently push in on the bulb and turn the bulb 1/4 turn counterclockwise.
4. Remove the bulb from the socket.

Scheme 186

1. Install the bulb to the socket.
2. Gently push in on the bulb and turn the bulb 1/4 turn clockwise.
3. Install the lens to the lamp assembly. CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the screws in order to retain the lens to the lamp assembly. Tighten Tighten the screws to 1.5 N.m (13 lb in).

Scheme 187

1. Remove the screws (4) that retain the license plate lamp to the license pocket.
2. Remove the license plate lamp (3) from the license pocket.
3. Disconnect the bulb socket (2) from the license plate lamp.
4. Remove the bulb (2) from the socket.

Scheme 188

1. Connect the bulb (2) into the socket.
2. Connect the bulb socket (2) into the license plate lamp.
3. Install the license plate lamp (3) to the license pocket. CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the license plate lamp retaining screws (4) to the license pocket. Tighten Tighten the screws to 2.5 N.m (22 lb in).

Scheme 189

1. Remove the upper quarter panel applique. Refer to «TAIL LAMP, BACK BODY OPENING APPLIQUE REPLACEMENT - SIDE»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-body-panels/#body-rear-end) .
2. Remove the nuts (2) that retain the tail lamp to, the upper quarter panel.
3. Remove the center high mounted stop lamp lens (2) from the center high mounted stop lamp applique (1).
4. Disconnect the bulb sockets from the tail lamp (3).
5. Remove the bulbs from the sockets by turning the bulbs in a counterclockwise direction.

Scheme 190

1. Install the bulbs into the sockets by turning the bulbs in a clockwise direction.
2. Connect the bulb sockets into the tail lamp (3). CAUTION: Refer to «FASTENER NOTICE»(/chevrolet/chevy-express-h2500/2003-2003/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
3. Install the tail lamp retaining nuts (2) to the upper quarter panel. Tighten Tighten the nuts to 5 N.m (44 lb in).
4. Install the upper quarter panel applique. Refer to «TAIL LAMP, BACK BODY OPENING APPLIQUE REPLACEMENT - SIDE»(/chevrolet/chevy-express-h2500/2003-2003/remont/exterior-body-panels/#body-rear-end) .

Exterior Lamps

The exterior lighting system consist of the following lamps

1. The headlamps
2. The daytime running lamps (DRL)
3. The park, tail and marker lamps
4. The turn signal/hazard lamps
5. The stop lamps
6. The backup lamps

Headlamps

Headlamp ON/OFF control is determined by the body control module (BCM) by a signal on the headlamp switch on input circuit when the headlamp switch is in the HEAD position.

If the headlight switch is left in the ON position, the inadvertent power control feature will turn off the headlights approximately 10 minutes after the ignition switch is turned to the OFF position. If the driver places the headlight switch in the ON position after the ignition switch has been turned OFF, or if the ignition switch is in the ACCY position, the headlights will remain on until turned off or the battery runs dead.

The high beam indicator is illuminated when the instrument cluster receives a class 2 serial data message from the BCM that the high beams are illuminated.

High Beams

The high beam headlamps receive voltage from the headlamp high relay located in the underhood fuse block. The BCM controls the relay on the headlamp high beam relay control circuit. High beam control is determined by a signal on the headlamp dimmer switch signal circuit from the multifunction switch. When the headlamp dimmer switch signal circuit is grounded, the BCM grounds the headlamp high beam relay control circuit, illuminating the high beam headlamps. The right and left high beam circuits are independent and are fused independently in the underhood fuse block. The right and left headlamps are grounded at G100 and G101.

Low Beams

The low beam headlamps receive voltage from the headlamp low relay located in the underhood fuse block. The BCM controls the relay on the headlamp low beam relay control circuit. Low beam control is determined by a signal on the headlamp dimmer switch signal circuit from the multifunction switch. When the headlamp dimmer switch signal circuit is open, the BCM grounds the headlamp low beam relay control circuit, illuminating the low beam headlamps. The right and left low beam circuits are independent and are fused independently in the underhood fuse block. The right and left headlamps are grounded at G100 and G101.

Daytime Running Lamps (DRL)

The DRL are a function of the front turn signal lamps. The DRL will operate when the ignition switch is in the RUN position, the gear selector is not in the PARK position, and the headlamp switch is in the OFF position. When the BCM receives these signals it will signal the turn/hazard flasher module to turn on the DRL by grounding the DRL low control signal. The turn/hazard flasher module supplies voltage to the DRL on the right and left DRL/turn supply voltage circuits. If a front turn signal lamp is inoperative the DRL will not operate.

The DRL can be deactivated by turning the headlamp switch to the DRL OFF position while the DRL are operating. The DRL defeat position of the headlamp switch is a momentary ground signal to the BCM to command the DRL function ON or OFF. After each key cycle the BCM will default to the DRL ON function.

Park, Tail and Marker Lamps

The park, tail and marker lamps, including the license lamps, are turned on when the headlamp switch is placed in the PARK or HEAD position. The headlamp and panel dimmer switch supplies a ground signal to the BCM on the park lamps switch on signal circuit. The underhood fuse block supplies battery positive voltage to both the park lamp relay switch contacts and the park lamp coil circuit. The body control module (BCM) provides a ground or control circuit to the park lamp relay coil circuit. When the park lamps are turned on the BCM energizes the park lamp relay. Current flow is from the park lamp relay to these fuses in the body fuse block

1. FR PARK
2. LR PARK
3. RR PARK
4. TRLR PARK
5. UPFTR PRK

The front park and marker lamps are grounded at G100 and G101. The rear park and license lamps are grounded at G401 and 402.

Turn Signal/Hazard Lamps

The IGN E 10 A fuse in the underhood fuse block supplies battery positive voltage to the turn signal switch assembly and ground for the hazard switch is from G302. The FLASHER 15 A fuse in the underhood fuse block supplies battery positive voltage to the turn/hazard flasher module. When the turn signal switch is placed in either the left or right position, a voltage signal is completed from the turn signal switch to the turn/hazard flasher module. When the hazard flasher switch is activated, a ground signal is completed from the hazard switch to the turn/hazard flasher module. The turn/hazard flasher module then sends an on-off voltage signal to the appropriate turn signal lamps, or to all turn signal lamps for hazard operation through these fuses

1. DR TRN MIR, in the body fuse block
2. PASS TRN MIR, in the body fuse block
3. LR STOP/TRN, in the body fuse block
4. RR STOP/TRN, in the body fuse block
5. LR TURN in the underhood fuse block
6. RR TURN in the underhood fuse block
7. LT DRL/TRN in the underhood fuse block
8. RT DRL/TRN in the underhood fuse block

The audio chime is also activated when the turn signals are on. When the hazard switch is pressed, all turn signal lamps will flash including both IPC turn indicators. The front turn signals are grounded at G100 and G101. The rear turn signals are grounded at G401 and 402. The mirror turn signals are grounded through a splice pack at G347.

Stop Lamps

The STOP LP 15 A fuse in the underhood fuse block supplies battery positive voltage to the normally open stop lamp switch. When the driver presses the brake pedal, the switch contacts close and battery positive voltage is supplied to the STOP/CHMSL fuse and through the turn/hazard flasher module to the LR STOP/TRN and RR STOP/TRN fuses in the body fuse block and the LR TURN and RR TURN fuses in the underhood fuse block. The voltage from the STOP/CHMSL fuse is to the CHMSL and cruise control. The voltage from the LR STOP/TRN and RR STOP/TRN fuses is to the rear stop lamps. The voltage from the LR TURN and RR TURN fuses is to the trailer stop/turn relays. The rear stop lamps are grounded at G401 and 402. The CHMSL is grounded at G401

Backup Lamps

The B/U LP 20 A fuse in the underhood fuse block supplies battery positive voltage to the normally open park neutral position (PNP) switch. When driver places the gear selector lever is in the REVERSE position, the switch closes and the voltage is from the switch to the powertrain control module (PCM). The PCM signals the BCM on the class II serial data circuits that the backup lamps are requested. The BCM supplies voltage on the backup lamp supply voltage circuit to the backup lamps and to the automatic day/night mirror. The backup lamps are grounded at G401. Voltage for the backup lamp supply voltage, courtesy lamp supply voltage, as well as the courtesy lamp high control circuits is from the TBC 2 fuse 18 in the underhood fuse block directly through the BCM to these circuits.

Interior Lamps

The interior lighting consist of the following 2 groups. This first group includes lamps that may not be dimmed.

1. Courtesy/illuminated entry lamps
2. Dome lamps
3. Reading lamps
4. Vanity mirror lamps

Courtesy/Illuminated Entry Lamps (Without YF7 RPO Code)

The courtesy/illuminated entry lamps, may be manually turned on or off by placing the interior lamp switch in the ON or OFF position. When the driver places the dome lamp defeat switch in the OFF position, the courtesy/illuminated entry lamps will be disabled. If a door is opened, the courtesy/illuminated entry lamps illuminate. After all the doors have been closed the courtesy/illuminated entry lamps will remain illuminated approximately 15 seconds. The courtesy/illuminated entry lamps will also turn on prior to any door being opened, and remain illuminated approximately 40 seconds when the driver removes the ignition key.

The courtesy lamps are controlled and receive voltage from the BCM. The BCM receives signals from the mini wedges and door jamb switches when a door is opened or anytime the courtesy lamp on switch is placed in the ON position. Ground is provided to the cargo mini wedge at G402. Ground is provided to the remaining switches as well as all courtesy, reading and vanity lamps at G347.

Voltage for the courtesy lamp supply voltage and the backup lamp supply voltage circuits is from the TBC 2 fuse 18 in the underhood fuse block directly through the BCM to these circuits.

Courtesy/Illuminated Entry Lamps (With YF7 RPO Code)

The courtesy/illuminated entry lamps, may be manually turned on or off by placing the interior lamp switch in the ON or OFF position. When the driver places the dome lamp defeat switch in the OFF position, the courtesy/illuminated entry lamps will be disabled. If an outside door handle is lifted or a door is opened, the courtesy/illuminated entry lamps illuminate. After all the doors have been closed the courtesy/illuminated entry lamps will remain illuminated approximately 15 seconds. The courtesy/illuminated entry lamps will also turn on prior to any door being opened, and remain illuminated approximately 40 seconds when the driver removes the ignition key.

The body fuse block supplies battery positive voltage to the courtesy lamp relay switch contacts. Ground is supplied to the courtesy lamp relay coil contact. The BCM supplies voltage on the courtesy lamp high control circuit to energize the courtesy lamp relay and supply voltage to the courtesy lamps. The BCM receives signals from the mini wedges and door jamb switches any time a door is opened, and anytime the courtesy lamp on switch is placed in the ON position. Ground is provided to the cargo mini wedge at G402. Ground is provided to the remaining switches as well as the stepwell lamps at G347.

Voltage for the courtesy lamp high control and the backup lamp supply voltage circuits is from the TBC 2 fuse 18 in the underhood fuse block directly through the BCM to these circuits.

Keyless Entry Interior Illumination

When the driver uses the door key in order to unlock the doors, the body control module (BCM) receives a door unlock signal. The BCM must have inputs that indicate that the ignition switch is OFF, the courtesy lamp switch is OFF and all the doors are closed. The BCM will then activate the interior lamps. The courtesy lamps will remain on, approximately 15 seconds after the door is closed. If the door locks are activated to the LOCK position, or if the ignition switch is turned to either the RUN or CRANK position the courtesy lamps will turn off immediately.

When the driver uses the remote function actuator transmitter to unlock the doors, trunk or presses the panic button, the BCM will keep the courtesy lamps on approximately 40 seconds. When the driver uses the remote function actuator transmitter to lock the doors, the BCM will keep the courtesy lamps on approximately 2 seconds. If the ignition switch is turned to either the RUN or CRANK position the courtesy lamps will turn off immediately. The BCM will also keep the courtesy lamps on approximately 40 seconds, after an alarm event is completed.

Vanity Lamps

The inadvertent supply voltage circuit of the BCM provides battery positive voltage to each vanity mirror lamp. When the vanity mirror cover on the sunshade is opened, a switch closes to provide a ground circuit and the vanity lamp illuminates. Ground is provided to the vanity lamps at G347.

Voltage for the inadvertent supply voltage circuit is from the TBC 4 fuse 11 in the underhood fuse block directly through the BCM to this circuit.

Reading Lamps

The inadvertent power supply voltage circuit of the BCM provides battery positive voltage to the reading lamps. The reading lamps and switch are integral to the courtesy/reading lamp assembly. When the switch is closed, voltage is supplied and the lamp illuminates. Ground is provided to the reading lamps at G347.

Voltage for the inadvertent supply voltage circuit is from the TBC 4 fuse 11 in the underhood fuse block directly through the BCM to this circuit.

Dome Fluorescent Work Lamps

The DOME FLUORESCENT WORK LAMPS Fuse 10A fuse in the rear fuse block, supplies battery positive voltage to the dome fluorescent work lamps. Each dome fluorescent work lamp has it own integral on/off switch. When the dome fluorescent work lamp switch is turned on, ground is provided and the lamp illuminates. The dome fluorescent work lamp switches are grounded at G106.

Battery Rundown Protection/Inadvertent Power

The BCM inadvertent power supply voltage circuit provides battery positive voltage to all of the interior reading lamps, underhood lamp, and both visor vanity mirror lamps. In the event that any of these lamps were to remain illuminated for a period of more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power supply voltage circuit to prevent a total battery discharge condition. Only when the ignition switch is cycled back to the RUN position will the BCM reset the internal timer and reactivate the inadvertent power courtesy lamps supply voltage circuit.

The BCM also utilizes the inadvertent power courtesy lamps supply voltage circuit as a courtesy lamp request signal circuit when none of the lamps in the circuit are illuminated. When a lamp switch is activated, the BCM receives the request for lamp illumination and switches to supplying voltage to the inadvertent power courtesy lamps supply voltage circuit.

Interior Lamps Dimming

The second group includes lamps which may be dimmed. This group may use a combination of vacuum fluorescent (VF) illumination and incandescent lamps.

When the ignition switch is turned to the RUN position, the radio's vacuum fluorescent (VF) displays turn on at maximum brightness. When the park lamps are on, all incandescent back lighting turn on at the dimming level indicated by the instrument panel (I/P) dimmer switch. At the same time all vacuum fluorescent (VF) displays dim to match the indicated dimming level. The panel dimmer switch potentiometer is an input to the BCM. When the driver selects a dimming setting by moving the I/P dimming switch potentiometer, all incandescent back lighting lamps are provided with a specific voltage. When the I/P dimmer switch is moved from MIN to MAX, all vacuum fluorescent (VF) displays, as well as all incandescent back lighting respond from minimum intensity to maximum brightness in response to the I/P dimmer switch.

1. The instrument panel cluster (IPC)
2. The radio controls
3. The headlamp and panel dimmer switch
4. The HVAC control assemblies
5. The inflatable restraint disable switch
6. The tow/haul switch
7. The window and door lock switches
8. The rear heater switch
9. The rear seat audio control

The I/P cluster illumination lamps, various switches and control assemblies receive voltage and are controlled by the BCM on the instrument panel lamps dimming control circuit and the backlight lamps control circuit.

Voltage for the LED dimming signal, instrument panel lamps dimming control, as well as the backlight lamps control circuits is from the TBC 3 fuse 16 in the underhood fuse block directly through the BCM to these circuits.

Scheme 191

See also:
• TESTING FOR INTERMITTENT AND POOR CONNECTIONS
• CHECKING AFTERMARKET ACCESSORIES
• BATTERY DISCONNECT CAUTION
• BATTERY NEGATIVE CABLE DISCONNECT/CONNECT PROCEDURE
• TRIM PLATE BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER
• KNEE BOLSTER BRACKET REPLACEMENT - LEFT
• GRILLE REPLACEMENT (UPLEVEL)
• HALOGEN BULB CAUTION
• FASTENER NOTICE
• TAIL LAMP, BACK BODY OPENING APPLIQUE REPLACEMENT - SIDE
• Diagnostic System Check - Lighting Systems