Pinpoint Test I: One Or More Stoplamps Are Inoperative
Stoplamps
Pinpoint Test I: One Or More Stoplamps Are Inoperative
Refer to Wiring Diagram Set 90, Turn Signal/Stop/Hazard Lamps for schematic and connector information Electrical Diagrams.
Normal Operation - 4-Door
When the brake pedal is applied, voltage is routed to the high mounted stoplamp and to the LH and RH turn relays. The voltage passes through the turn relays, on to the LH and RH stoplamps. When a turn relay is energized (during turn lamp operation), voltage from the stoplamp switch is interrupted. The stoplamps are combination rear stop/turn lamps.
5-Door
On 5-door vehicles, when the brake pedal is applied, voltage is routed to all of the stoplamps.
- DTC B132B:14 (Left Stop/Turn Lamp: Circuit Short To Ground Or Open)- a continuous and on-demand DTC that sets when the BCM (Body Control Module) detects a short to ground from the LH rear turn lamp relay coil ground controlled circuit.
- DTC B132C:14 (Right Stop/Turn Lamp: Circuit Short To Ground Or Open)- a continuous and on-demand DTC that sets when the BCM (Body Control Module) detects a short to ground from the RH rear turn lamp relay coil ground controlled circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Bulb socket
- High mounted stoplamp
- Turn relay
- BCM (Body Control Module)
PINPOINT TEST I : ONE OR MORE STOPLAMPS ARE INOPERATIVE
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
I1 DETERMINE THE INOPERATIVE STOPLAMP
- Ignition OFF.
- Apply the brake pedal and observe the stoplamps.
Are all the stoplamps inoperative?
Yes
GO to Pinpoint Test H Pinpoint Test H: All The Stoplamps Are Inoperative.
No
For an inoperative high mounted stoplamp, GO to I2.
For an inoperative rear lamp on a 5-door vehicle, GO to I4.
For an inoperative rear lamp on a 4-door vehicle, GO to I6.
I2 CHECK FOR VOLTAGE TO THE HIGH MOUNTED STOPLAMP
- Disconnect: High Mounted Stoplamp C904 or C9040.
- For 4-door vehicles, while applying the brake pedal, measure the voltage between the high mounted stoplamp C904-1, circuit CCA26 (BU/GY), harness side and ground.
- For 5-door vehicles, while applying the brake pedal, measure the voltage between the high mounted stoplamp C9040-1, circuit CCA26 (BU/GY), harness side and ground.
Is the voltage greater than 10 volts?
Yes
GO to I3.
No
REPAIR circuit CCA26 (BU/GY) for an open. TEST the system for normal operation.
I3 CHECK THE HIGH MOUNTED STOPLAMP GROUND CIRCUIT FOR AN OPEN
- For 4-door vehicles, while applying the brake pedal, measure the voltage between the high mounted stoplamp C904-1, circuit CCA26 (BU/GY), harness side and the high mounted stoplamp C904-2, circuit GD143 (BK/VT), harness side.
- For 5-door vehicles, while applying the brake pedal, measure the voltage between the high mounted stoplamp C9040-1, circuit CCA26 (BU/GY), harness side and the high mounted stoplamp C9040-2, circuit GD143 (BK/VT), harness side.
Is the voltage greater than 10 volts?
Yes
INSTALL a new high mounted stoplamp. REFER to High Mounted Stoplamp Service and Repair. TEST the system for normal operation.
No
REPAIR circuit GD143 (BK/VT) for an open. TEST the system for normal operation.
I4 CHECK FOR VOLTAGE TO THE REAR LAMP
- Disconnect: Inoperative Rear Lamp.
- While applying the brake pedal, measure the voltage between the LH rear lamp C414-3, circuit CCA26 (BU/GY), harness side and ground; or between the RH rear lamp C417-3, circuit CCA26 (BU/GY), harness side and ground.
Is the voltage greater than 10 volts?
Yes
GO to I5.
No
REPAIR circuit CCA26 (BU/GY) for an open. TEST the system for normal operation.
I5 CHECK THE REAR LAMP GROUND CIRCUIT FOR AN OPEN
- While applying the brake pedal, measure the voltage between the LH rear lamp C414-3, circuit CCA26 (BU/GY), harness side and the LH rear lamp C414-1, circuit GD143 (BK/VT), harness side; or between the RH rear lamp C417-3, circuit CCA26 (BU/GY), harness side and the RH rear lamp C417-1, circuit GD145 (BK/BU), harness side.
Is the voltage greater than 10 volts?
Yes
REPAIR or INSTALL a new rear lamp harness. TEST the system for normal operation.
No
REPAIR circuit GD143 (BK/VT) (LH rear lamp) or circuit GD145 (BK/BU) (RH rear lamp) for an open. TEST the system for normal operation.
I6 CHECK FOR VOLTAGE TO THE BULB SOCKET
- Disconnect: Inoperative Rear Lamp.
- While applying the brake pedal, measure the voltage between the LH rear lamp C412-3, circuit CLS55 (GN/BU), harness side and ground; or between the RH rear lamp C415-3, circuit CLS54 (BU/OG), harness side and ground.
Is the voltage greater than 10 volts?
Yes
GO to I7.
No
GO to I8.
I7 CHECK THE REAR LAMP GROUND CIRCUIT FOR AN OPEN
- While applying the brake pedal, measure the voltage between the LH rear lamp C412-3, circuit CLS55 (GN/BU), harness side and the LH rear lamp C412-1, circuit GD143 (BK/VT), harness side; or between the RH rear lamp C415-3, circuit CLS54 (BU/OG), harness side and the RH rear lamp C415-1, circuit GD145 (BK/BU), harness side.
Is the voltage greater than 10 volts?
Yes
INSTALL a new bulb socket. TEST the system for normal operation.
No
REPAIR circuit GD143 (BK/VT) (LH rear lamp) or circuit GD145 (BK/BU) (RH rear lamp) for an open. TEST the system for normal operation.
I8 CHECK THE TURN RELAY
- Connect: Inoperative Rear Lamp.
- Disconnect: Suspect Turn Relay.
- Substitute a known good relay.
- Apply the brake pedal and observe the stoplamps.
Does the stoplamp in question illuminate?
Yes
REMOVE the known good relay. INSTALL a new turn relay. TEST the system for normal operation.
No
REMOVE the known good relay. GO to I9.
I9 CHECK FOR VOLTAGE TO THE TURN RELAY
- For the LH stoplamp, while applying the brake pedal, measure the voltage between the LH turn relay pin 4, circuit CCA26 (BU/GY), CJB (Central Junction Box) face side and ground.
- For the RH stoplamp, while applying the brake pedal, measure the voltage, between the RH turn relay pin 4, circuit CCA26 (BU/GY), CJB (Central Junction Box) face side and ground.
Is the voltage greater than 10 volts?
Yes
GO to I10.
No
REPAIR circuit CCA26 (BU/GY) for an open. TEST the system for normal operation.
I10 BYPASS THE TURN RELAY
- For the LH stoplamp, connect a fused jumper wire between the LH turn relay pin 4, circuit CCA26 (BU/GY), CJB (Central Junction Box) face side and the LH turn relay pin 3, circuit CLS55 (GN/BU), CJB (Central Junction Box) face side.
- For the RH stoplamp, connect a fused jumper wire between the RH turn relay pin 4, circuit CCA26 (BU/GY), CJB (Central Junction Box) face side and the LH turn relay pin 3, circuit CLS54 (BU/OG), CJB (Central Junction Box) face side.
- Apply the brake pedal and observe the stoplamps.
Does the stoplamp in question illuminate?
Yes
REMOVE the jumper wire. GO to I11.
No
REMOVE the jumper wire. REPAIR circuit CLS55 (GN/BU) (LH rear lamp) or circuit CLS54 (BU/OG) (RH rear lamp) for an open. TEST the system for normal operation.
I11 CHECK THE TURN RELAY COIL GROUND CIRCUIT FOR A SHORT TO GROUND
- Disconnect: BCM (Body Control Module) C2280D.
- For the LH stoplamp, measure the resistance between the LH turn relay pin 2, circuit CLS51 (WH/GN), harness side and the ground.
- For the RH stoplamp, measure the resistance between the RH turn relay pin 2, circuit CLS53 (GY/VT), harness side and the ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to I12.
No
REPAIR circuit CLS51 (WH/GN) (LH stoplamp) or circuit CLS53 (GY/VT) for a short to ground. CLEAR the DTCs. TEST the system for normal operation.
I12 CHECK FOR CORRECT BCM (Body Control Module) OPERATION
- Disconnect all the BCM (Body Control Module) connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the BCM (Body Control Module) connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new BCM (Body Control Module). TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.