Lighting Systems: Other Chevrolet SSR I

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Backup Lamps Always On

Backup Lamps Always On

Backup Lamps Inoperative

Backup Lamps Inoperative

Courtesy Lamps Always On

Courtesy Lamps Always On

Courtesy Lamps Inoperative

Courtesy Lamps Inoperative

Daytime Running Lamps (DRL) Always On

Daytime Running Lamps (DRL) Always On

Daytime Running Lamps (DRL) Inoperative

Daytime Running Lamps (DRL) Inoperative

Fog Lamp Indicator Inoperative

Fog Lamp Indicator Inoperative

Fog Lamps Always On

Fog Lamps Always On

Fog Lamps Inoperative

Fog Lamps Inoperative

Hazard Lamps Always On

Hazard Lamps Always On

Hazard Lamps Inoperative

Hazard Lamps Inoperative

Headlamps Always On - Low or High Beam

Headlamps Always On - Low or High Beam

Headlamps Inoperative - High Beams

Headlamps Inoperative - High Beams

Headlamps Inoperative - Low Beams

Headlamps Inoperative - Low Beams

Headlamps Inoperative - Flash to Pass

Headlamps Inoperative - Flash to Pass

High Beam Indicator Always On

High Beam Indicator Always On

High Beam Indicator Inoperative

High Beam Indicator Inoperative

Interior Backlighting Does Not Dim

Interior Backlighting Does Not Dim

Interior Backlighting Inoperative

Interior Backlighting Inoperative

Instrument Panel (I/P) Compartment Lamp Inoperative

Instrument Panel (I/P) Compartment Lamp Inoperative

Instrument Panel (I/P) Compartment Lamp Always On

Instrument Panel (I/P) Compartment Lamp Always On

License Lamps Inoperative

License Lamps Inoperative

Marker Lamps Inoperative

Marker Lamps Inoperative

Park Lamps Inoperative

Park Lamps Inoperative

Stop Lamps Always On

Stop Lamps Always On

Stop Lamps Inoperative

Stop Lamps Inoperative

Tail Lamps Inoperative

Tail Lamps Inoperative

Tail, Marker, and License Lamps Always On

Tail, Marker, and License Lamps Always On

Tail, Marker, and License Lamps Inoperative

Tail, Marker, and License Lamps Inoperative

Turn Signal Lamps and/or Indicators Always On or Flashing

Turn Signal Lamps and/or Indicators Always On or Flashing

Turn Signal Lamps and/or Indicators Inoperative

Turn Signal Lamps and/or Indicators Inoperative

Vanity Mirror Lamp(s) Inoperative

Vanity Mirror Lamp(s) Inoperative

Screen Method for Headlamp Aiming

The screen method requires an area set up specifically for headlamp aiming.

Scheme 21

The area should consist of a level surface large enough to allow for a vehicle and an additional 7.62 m (25 ft) as measured from the face of the headlamps to the aiming screen.

Scheme 22

The screen should be a wall or other flat surface at least 1.52 m (5 ft) high by 3.66 m (12 ft) wide with a matte white surface, well shaded from extraneous light, and 90 degrees to the floor. The screen should be provided with a permanent vertical reference line 0.61 m (2 ft) from the left edge of the screen, 2 laterally adjustable vertical tapes, and 1 vertically adjustable horizontal tape.

After the aiming screen has been set up and located, paint or tape a reference line on the floor 15.24 m (50 ft) from the vertical reference line on the screen. This line should be perpendicular to the aiming screen and a mark placed at 7.62 m (25 ft) from the screen.

Headlamp Aiming Procedure

1. Align the left tires of the vehicle with the reference line extending from the screen with the headlamps aligned with the reference line.
2. Remove any snow, ice, or mud from the vehicle.
3. The vehicle must be fully assembled and all other work stopped while the headlamp aiming is being done.
4. The vehicle must contain one person or approximately 73 kg (160 lb).
5. Tires should be properly inflated.
6. Rock the vehicle to stabilize the suspension.
7. At the screen, measure from the floor and place the horizontal tape at the above measured distance.
8. Turn the low beam headlamps ON.
9. The graphic shows the vertical (1) adjustment, no horizontal adjustments are required. Adjust the headlamps to the specifications required by state and local authorities.
10. The beam pattern must be positioned as shown in the graphic.
11. Adjust one headlamp at a time while blocking the light from the other. The cover must be away from the headlamp. Refer to the following: The low beam centerline reference mark (4) Distance from ground to the low beam bulb centerline reference mark (1) The ground line (2) Horizontal edge of the low beam headlamp pattern (3) The edge of the headlamp pattern (3), must be 5 cm (2 in) below the reference mark (4), with the vehicle 7.62 m (25 ft) away.

Fog Lamp Aiming Procedure

Proper road illumination and safety require the fog lamps to be aimed. The front fog lamp aim should be checked when a new front fog lamp assembly is installed, or if any service repairs have been performed to the vehicle which disturb the front fog lamp mounting or the vehicle ride height.

There are no horizontal adjustments for aiming the front fog lamp assemblies on this vehicle.

Scheme 23

The front fog lamps can be adjusted by turning the adjustment screw (1) located below the backside of the lamp, next to the electrical connector.

Use the following guidelines in order to adjust the aim

1. Turn the TORX® adjustment screw clockwise in order to raise the aim.
2. Turn the TORX® adjustment screw counterclockwise in order to lower the aim.

1. To ensure accurate vertical front fog lamp aiming, first perform the following steps to prepare the vehicle. Make sure that all the components are in place on the vehicle, the tires are properly inflated, and there is not any mud or snow clinging to the vehicle. Stop all other operations of work on the vehicle. Make sure the fuel level is 1/2 full or more. Jounce the vehicle to settle the suspension. Place the vehicle on a level surface 7.6 m (25 ft) from the target screen. Measure the distance from the floor to the center of the fog lamp (5). Using this measurement, mark the horizontal centerline of the fog lamp (1) on the target screen directly in front of the vehicle. Start the vehicle in order to level the suspension.
2. Turn the front fog lamps ON.
3. Access the fog lamp vertical adjuster.
4. Adjust the fog lamp up or down until the top edge of the high intensity zone on the screen is 102 mm (4 in) below (2) the horizontal centerline (1).
5. Turn OFF the front fog lamps.

Exterior Lamps

The exterior lighting system consist of the following lamps

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

Headlamps

The headlamp low beam relay provides electrical power to the vehicle low beam headlamps. The relay is controlled by a ground signal from the body control module (BCM). The BCM determines the desired lamp operation using the ambient light sensor, multifunction switch, wiper motor, and the park brake switch as inputs.

Major components of this system are the BCM, headlamps, low beam relay, high beam relay, ambient light sensor, multifunction switch, park brake switch, and wiper motor.

The headlamps may be turned on in 3 different ways. First, when the driver places the headlamp switch in the HEADLAMP position, normal operation occurs. Second, with the headlamp switch is placed in the AUTO position, automatic lamp control (ALC) occurs. During ALC control, the headlamps will be in daytime running lamp (DRL) operation in daylight conditions, or low beam operation in low light conditions. Third, in wiper activated headlamp (WAH) mode. Only when the wiper system is activated while the vehicle is in gear, the wiper blades have completed at least 3 cycles, and then a 35 second time period expires, will the BCM switch from DRL mode to headlamp mode during daylight conditions. When the gearshift lever is placed in the PARK or NEUTRAL position or if the wipers are turned OFF, normal manual or ALC operation will resume after approximately 60 seconds.

The low and high beam relays receive battery positive voltage directly from the battery. The BCM supplies a ground signal to the low beam relay for automatic headlight control and normal headlight operation. The BCM also supplies ground to the high beam relay coil for high beam headlight operation. When the driver places the headlamp switch in the HEADLAMP position and the dimmer switch is in the low beam position, the low beam relay sends current flow through the left and right low beam headlamp fuses to both low beam headlamps. The dimmer switch sends a ground signal to the BCM in the high beam position and a momentary ground signal in the flash to pass (FTP) position from G103 to deactivate the low beam headlights and activate the high beam headlights. With the headlights in the low beam position, the high beams may be momentarily turned on or flashed by activating the FTP portion of the switch.

The instrument panel cluster (IPC) illuminates the high beam indicator when the BCM detects that the high beams are requested. The IPC receives a class 2 message from the BCM requesting illumination.

The Headlamps On at Exit and Perimeter Lighting modes can be adjusted using the steering wheel controls to select the desired function as displayed in the driver information center. The Headlamps On at Exit selection will allow the driver to customize the period of time that the headlamps remain illuminated upon exiting the vehicle. This period can be adjusted from 0 seconds to 180 seconds. The Perimeter Lighting feature allows the driver to select if they desire the headlamps and backup lamps to illuminate when the door UNLOCK button on the key fob is activated. This feature can be turned ON or OFF by using the driver information center steering wheel control buttons.

Daytime Running Lamps (DRL)

The ambient light sensor is a light sensitive transistor that varies its voltage signal to the body control module (BCM) in response to changes to the outside (ambient) light level. When the BCM receives this signal it will either turn on the low beam headlamps at a reduced intensity for daytime running lamp (DRL) operation through the DRL diode and the 2 DRL relays or the headlamps, through the low beam relay, at full intensity including all the appropriate exterior lamps, for auto headlamp operation. The low beam headlights, alone at a reduced intensity, are utilized as the DRL. Any function or condition that turns ON the headlights will cancel the DRL operation. With the headlight switch in the OFF position, the headlights will either be turned ON or OFF, after an approximate 8 second delay, depending on whether daylight or low light conditions are sensed. When the BCM provides a ground for the 2 DRL relays for DRL operation in daylight conditions, the DRL relays illuminate the low beam headlights only. The supply voltage to these relays is reduced by the DRL diode. The DRL will operate when the ignition switch is in the RUN position, the gear selector is not in the PARK position and the parking brake is released. When these conditions have been met and the ambient light sensor indicates daytime conditions, the DRL mode will be activated.

Fog Lamps

With both the ignition switch in the RUN position and the park lamps or low beam head lamps on, the fog lights will illuminate when the driver presses the fog lamp switch. The FOG LP fuse in the underhood fuse block supplies battery positive voltage to the fog lamp relay. With the headlamp switch in either the park or headlamp position and the fog lamp switch is pressed, the body control module (BCM) will energize the fog lamp relay control circuit. The current flow is from the fog lamp relay to both front fog lamps and to ground G100 and G105. The state of the fog lamps either ON or OFF will remain the same until the fog lamp switch is pressed again, or the ignition switch is cycled OFF and ON. Fog lamp operation will be cancelled whenever the park lamps are turned OFF or the high beam headlights have been selected.

Park, Tail, Marker, and License Lamps

The park, tail, marker, and license lamps are turned on when the headlamp switch is placed in the PARK or ON position or anytime the headlights are requested. Battery positive voltage is supplied 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. When the park lamps are turned ON, the BCM energizes the park lamp relay. Current flow is from the park lamp relay to the individual park lamp circuit fuses and to their respective park, tail, marker, and license lamps. The front park lamps are grounded at G105 and G100. The tail lamps and license lamps are grounded at G402. If the driver places the headlight switch in the ON position after the ignition switch has been turned OFF, the park, tail, marker, and license lamps will remain ON until turned OFF or the battery runs dead.

The TR-PRK fuse in the rear fuse block supplies battery positive voltage to a separate park lamp circuit connected to the trailer wiring harness.

Turn Signal Lamps

The smart flasher (GMSF) is an automotive flasher designed to accept turn, hazard, and brake inputs. The GMSF will provide corresponding outputs to the exterior lamps and instrument panel turn signal indicator lamps. This lighting system has combined lamps for the turn/hazard functions and the brake function. The system incorporates the use of flash rates for diagnostics. The flash rate is a calculation of the number of flashes that occur within a 60 second period. This system uses a percentage of on-time to off-time called duty cycle. For the bulb outage condition, the indicator of the vehicle side on which the outage occurs shall assume bulb outage flash rate mode. The opposite side indicator will assume the normal flash rate mode for an input from the non bulb outage side of the vehicle. Hazard warning lamp outage will maintain a normal flash rate as long as 2 or more exterior signaling lamps are functional. During all modes of operation, the instrument panel cluster (IPC) will receive the same flash rates and duty cycles that the exterior lamps receive. The IPC will then control the indicators in the cluster. The vehicle operator will be provided with an audible and visual indication of the flasher operation. Below is a table with flash rates and duty cycles

Exterior Lighting Systems Description and Operation

The IGN E fuse in the underhood fuse block supplies Ignition positive voltage to the turn signal switch assembly. With the ignition switch in the RUN or START position, ignition positive voltage is connected through the turn signal/multifunction switch assembly to the GMSF which is powered by the FLASH fuse also in the underhood fuse block and is grounded at G200. When the turn signal switch is placed in either the left or right position, the circuit is completed from the GMSF to the turn signal lamps and to ground. The GMSF then sends an ON-OFF voltage signal to either the left or right turn signals and their IPC indicator. When the hazard switch is pressed, all turn signal lamps will flash including both IPC turn indicators. The front turn signals are grounded at G105 and G100. The rear turn signals are grounded at G402.

The IPC illuminates the TURN SIGNAL ON indicator in the driver information center when the IPC determines that the turn signal is active for more than 1.2 km (0.75 mile). The IPC also sends a class 2 message to the radio in order to activate the audible warning.

For trailer wiring, the turn signal circuits are also connected to the trailer wiring harness.

Stop Lamps

The ST/LP 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 turn signal hazard flasher module and the VEH CHMSL fuse in the rear fuse block. The turn signal hazard flasher module provides the current flow to the stop/turn lamps which are grounded at G402. The center high mounted stop lamp (CHMSL) is also grounded at G402.

For trailer wiring, the stop lamp circuit is provided by the turn signal hazard flasher module to the trailer wiring harness.

Backup Lamps

On a vehicle equipped with an automatic transmission, the backup lamps request signal is sent from the powertrain control module (PCM) to the body control module (BCM) via class 2. This signal is based on the state of the park neutral position (PNP) switch. When the driver places the gear selector lever in the REVERSE position, a class 2 signal is sent from the PCM to the BCM requesting backup lamp illumination.

The BCM directly supplies voltage for backup lamp operation. The backup lamps are grounded at G402.

Interior Lamps

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

1. The courtesy lamps
2. The instrument panel (I/P) compartment lamp
3. The reading lamps
4. The vanity mirror lamps

Courtesy Lamps

The courtesy lamp supply voltage circuit provides voltage to the interior illumination lamps which are all located on the underside of the inside rear view mirror. If a door is opened, the courtesy lamps illuminate. After all the doors have been closed, the courtesy lamps will remain illuminated approximately 15 seconds after the last door closes. The courtesy lamps will also turn ON prior to any door being opened and will remain illuminated approximately 40 seconds when the driver removes the ignition key. The body control module (BCM) will immediately turn off the courtesy lamps if a door lock command is received with all of the doors closed, or if the ignition switch is turned to either the ON or RUN position.

Reading Lamps

The inadvertent courtesy lamp supply circuit provides voltage for the reading lamps that are on the underside of the inside rear view mirror. These lamps may be manually turned ON or OFF with the switches on the mirror.

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 and all the doors are closed. The BCM will then illuminate the courtesy lamps. The courtesy lamps will remain illuminated for 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 or presses the panic button, the BCM will keep the courtesy lamps ON for approximately 15 seconds. If the door locks are activated to the UNLOCK or LOCK position or 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 for approximately 40 seconds after an alarm event is completed.

Vanity Lamps

The inadvertent courtesy lamp supply circuit of the body control module (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.

I/P Compartment Lamp

The inadvertent courtesy lamp supply circuit of the body control module (BCM) also provides battery positive voltage to instrument panel (I/P) compartment lamp. When the I/P compartment is opened, a switch closes to provide a ground circuit and the I/P compartment lamp illuminates.

Battery Rundown Protection/Inadvertent Power

The body control module (BCM) inadvertent courtesy lamp supply circuit provides battery positive voltage to all of the interior reading lamps, 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 a period of more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent courtesy lamp supply 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 courtesy lamp supply circuit.

The BCM also utilizes the inadvertent courtesy lamp supply 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 courtesy lamp supply 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 of incandescent lamps.

1. Console, and instrument panel (I/P) switches
2. HVAC control head assembly
3. Radio and steering wheel controls
4. The instrument panel cluster (IPC)

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 I/P dimmer switch. At the same time all VF displays dim to match the indicated dimming level. The panel dimmer switch potentiometer is an input to the body control module (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. The incandescent back lighting lamps are then grounded at G200 and G300. When the I/P dimmer switch is moved from MIN to MAX, all VF displays, as well as all incandescent back lighting respond from minimum intensity to maximum brightness in response to the I/P dimmer switch.