Pinpoint Test H: One Or More Stoplamps Are Inoperative
Stoplamps
Pinpoint Tests
Pinpoint Test H: One Or More Stoplamps Are Inoperative
Refer to Wiring Diagram Set 90, Turn Signal/Stop/Hazard Lamps for schematic and connector information. Diagrams By Number
Refer to Wiring Diagram Set 140, Customer Access for schematic and connector information. Diagrams By Number
Normal Operation - Wagon
When the brake pedal is applied, the stoplamp switch routes voltage to the Smart Junction Box (SJB) and the high mounted stoplamp. When the SJB detects the brake pedal is applied, the SJB provides voltage to the LH and RH rear stoplamps. The LH and RH rear stoplamps share a ground separately from the high mounted stoplamp.
Cutaway and Stripped Chassis
When the brake pedal is applied, the stoplamp switch routes voltage to the SJB and the body builder connector. When the SJB detects the brake pedal is applied, the SJB provides voltage to the LH and RH rear stoplamps. Ground for the stoplamps is provided by the body builder.
NOTE: SJB fuse 6 (20A) supplies voltage for both rear stoplamps and all front and rear turn lamps.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Bulb holder
- High mounted stoplamp
- Body builder equipment
- SJB
PINPOINT TEST H: 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.
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H1 DETERMINE IF ALL THE STOPLAMPS ARE INOPERATIVE
NOTE: Make sure the SJB self-test has been carried out before beginning diagnostics. Following the diagnostic steps before carrying out the self-test can lead to an incorrect repair.
- Ignition OFF.
- Apply the brake pedal and observe the stoplamps.
- Are all the stoplamps inoperative?
Yes
GO to Pinpoint Test G. Pinpoint Test G: All The Stoplamps Are Inoperative
No
For cutaway and stripped chassis vehicles, GO to H2.
For wagon, GO to H11.
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H2 MONITOR THE STOPLAMP SWITCH INPUT (CUTAWAY AND STRIPPED CHASSIS)
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB DataLogger.
- Monitor the SJB stoplamp switch PID (GEM_BOO) while applying the brake pedal.
- Does the PID indicate the brake pedal is applied?
Yes
GO to H4.
No
GO to H3.
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H3 CHECK THE STOPLAMP SWITCH INPUT TO THE SJB (CUTAWAY AND STRIPPED CHASSIS VEHICLES)
- Ignition OFF.
- Disconnect: SJB C2280b.
- While applying the brake pedal, measure the voltage between the SJB C2280b-40, circuit CCB08 (VT/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to H22.
No
REPAIR circuit CCB08 (VT/WH) for an open. TEST the system for normal operation.
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H4 CHECK FOR VOLTAGE TO THE BODY BUILDER CONNECTOR (STOPLAMP SWITCH OUTPUT)
- Ignition OFF.
- Disconnect: Body Builder C432.
- While applying the brake pedal, measure the voltage between the body builder C432-3, circuit CCB08 (VT/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to H5.
No
REPAIR circuit CCB08 (VT/WH) for an open. TEST the system for normal operation.
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H5 CHECK FOR VOLTAGE TO THE BODY BUILDER CONNECTOR (SJB OUTPUT)
- While applying the brake pedal, measure the voltage between the body builder connector, harness side and ground as follows:
- Is the voltage greater than 10 volts?
Yes
The vehicle is operating correctly. REFER to the body builder manual to continue diagnosis.
No
VERIFY the SJB fuse 6 (20A) is OK. If OK, GO to H6.
If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. After the repair: Diagrams By Number
If no DTCs are present, TEST the system for normal operation.
If DTC B106E is present, CLEAR the DTCs and REPEAT the self-test (required to enable the stoplamp output driver if DTC B106E is present). TEST the system for normal operation.
If DTC B106F is present, INSTALL a new SJB. REFER to Multifunction Electronic Modules Service and Repair. TEST the system for normal operation.
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H6 CHECK THE RECORDED DTCs FROM THE SJB SELF-TEST (CUTAWAY AND STRIPPED CHASSIS VEHICLES)
- Check the recorded results from the SJB self-test.
- Is DTC B2045 or DTC B2047 present?
Yes
GO to H7.
No
GO to H8.
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H7 CHECK THE STOPLAMP OUTPUT CIRCUIT FOR AN OPEN (CUTAWAY OR STRIPPED CHASSIS)
- Disconnect: SJB C2280d.
- Measure the resistance between the body builder connector, harness side and the SJB, harness side as follows:
- Is the resistance less than 5 ohms?
Yes
GO to H22.
No
REPAIR output circuit in question for an open. TEST the system for normal operation.
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H8 ISOLATE THE BODY BUILDER EQUIPMENT AS THE CAUSE OF THE CIRCUIT SHORT
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB Self-Test.
- Clear the DTCs and repeat the self-test (required to enable the stoplamp output driver if DTC B106E is present).
- While applying the brake pedal, measure the voltage between the body builder connector, harness side and ground as follows:
- Is the voltage greater than 10 volts?
Yes
The vehicle is operating correctly. REPAIR the body builder equipment for the cause of the short to ground or the excessive current draw. REFER to the body builder manual to continue diagnosis.
No
GO to H9.
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H9 CHECK THE STOPLAMP OUTPUT CIRCUIT FOR A SHORT TO GROUND (CUTAWAY OR STRIPPED CHASSIS)
- Ignition OFF.
- Disconnect: Trailer Tow Stop/Turn Relays.
- Disconnect: SJB C2280d.
- Measure the resistance between the body builder connector, harness side and ground as follows:
- Is the resistance greater than 10,000 ohms?
Yes
GO to H10.
No
REPAIR the output circuit in question for a short to ground. After the repair:
If no DTCs are present, TEST the system for normal operation.
If DTC B106E is present, CLEAR the DTCs and REPEAT the self-test (required to enable the stoplamp output driver if DTC B106E is present). TEST the system for normal operation.
If DTC B106F is present, INSTALL a new SJB. REFER to Multifunction Electronic Modules Service and Repair. TEST the system for normal operation.
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H10 CHECK FOR DTC B106F
- Check the recorded results from the SJB self-test.
- Is DTC B106F present?
Yes
The vehicle is operating correctly. REPAIR the body builder equipment for the cause of the short to ground or the excessive current draw. After the repair, INSTALL a new SJB. REFER to Multifunction Electronic Modules Service and Repair. TEST the system for normal operation.
No
GO to H22.
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H11 DETERMINE IF THE HIGH MOUNTED STOPLAMP ILLUMINATES
- Apply the brake pedal and observe the stoplamps.
- Is the high mounted stoplamp illuminated?
Yes
GO to H14.
No
GO to H12.
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H12 CHECK FOR VOLTAGE TO THE HIGH MOUNTED STOPLAMP
- Disconnect: High Mounted Stoplamp C475.
- While applying the brake pedal, measure the voltage between the high mounted stoplamp C475-1, circuit CCB08 (VT/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to H13.
No
REPAIR circuit CCB08 (VT/WH) for an open. TEST the system for normal operation.
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H13 CHECK FOR VOLTAGE TO THE HIGH MOUNTED STOPLAMP USING THE GROUND PIN
- While applying the brake pedal, measure the voltage between the high mounted stoplamp C475-1, circuit CCB08 (VT/WH), harness side and the high mounted stoplamp C475-3, circuit GD133 (BK), 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 GD133 (BK) for an open. TEST the system for normal operation.
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H14 MONITOR THE STOPLAMP SWITCH INPUT (WAGON)
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB DataLogger.
- Monitor the SJB stoplamp switch PID (GEM_BOO) while applying the brake pedal.
- Does the PID indicate the brake pedal is applied?
Yes
GO to H16.
No
GO to H15.
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H15 CHECK THE STOPLAMP SWITCH INPUT TO THE SJB
- Ignition OFF.
- Disconnect: SJB C2280b.
- While applying the brake pedal, measure the voltage between the SJB C2280b-40, circuit CCB08 (VT/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to H22.
No
REPAIR circuit CCB08 (VT/WH) for an open. TEST the system for normal operation.
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H16 CHECK THE RECORDED DTCs FROM THE SJB SELF-TEST (WAGON)
- Check the recorded results from the SJB on-demand self-test.
- Is DTC B2045 or DTC B2047 present?
Yes
GO to H17.
No
GO to H20.
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H17 CHECK FOR VOLTAGE TO THE BULB HOLDER
- Ignition OFF.
- Disconnect: Inoperative Rear Lamp.
- While applying the brake pedal, measure the voltage between the LH rear lamp C4035-3, circuit CLS18 (GY/BN), harness side and ground; or between the RH rear lamp C4032-3, circuit CLS19 (VT/OG), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to H18.
No
GO to H19.
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H18 CHECK FOR VOLTAGE TO THE REAR STOPLAMP USING THE CONNECTOR GROUND
- While applying the brake pedal, measure the voltage between the LH rear lamp C4035-3, circuit CLS18 (GY/BN), harness side and the LH rear lamp C4035-1, circuit GD149 (BK/GY), harness side; or between the RH rear lamp C4032-3, circuit CLS19 (VT/OG), harness side and the RH rear lamp C4032-1, circuit GD149 (BK/GY), harness side.
- Is the voltage greater than 10 volts?
Yes
INSTALL a new bulb holder. TEST the system for normal operation.
No
REPAIR circuit GD149 (BK/GY) for an open. TEST the system for normal operation.
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H19 CHECK THE STOPLAMP OUTPUT CIRCUIT FOR AN OPEN
- Disconnect: SJB C2280d.
- Measure the resistance between the LH rear lamp C4035-3, circuit CLS18 (GY/BN), harness side and the SJB C2280d-25, circuit CLS18 (GY/BN), harness side; or between the RH rear lamp C4032-3, circuit CLS19 (VT/OG), harness side and the SJB C2280d-26, circuit CLS19 (VT/OG), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to H22.
No
REPAIR circuit CLS18 (GY/BN) (LH stoplamp) or circuit CLS19 (VT/OG) (RH stoplamp) for an open. TEST the system for normal operation.
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H20 ISOLATE THE BULB HOLDER AS THE CAUSE OF THE CIRCUIT SHORT
- Ignition OFF.
- Disconnect: Inoperative Rear Lamp.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB Self-Test.
- Clear the DTCs and repeat the self-test (required to enable the stoplamp output driver if DTC B106E is present).
- While applying the brake pedal, measure the voltage between the LH rear lamp C4035-3, circuit CLS18 (GY/BN), harness side and ground; or between the RH rear lamp C4032-3, circuit CLS19 (VT/OG), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
INSTALL a new bulb holder. TEST the system for normal operation.
No
GO to H21.
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H21 CHECK THE STOPLAMP OUTPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Trailer Tow Stop/Turn Relays.
- Disconnect: SJB C2280d.
- Measure the resistance between the SJB C2280d-25 (LH stoplamp output), circuit CLS18 (GY/BN), harness side and ground; or between the SJB C2280d-26 (RH stoplamp output), circuit CLS19 (VT/OG), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to H22.
No
REPAIR the circuit in question for a short to ground. After the repair:
If no DTCs are present, TEST the system for normal operation.
If DTC B106E is present, CLEAR the DTCs and REPEAT the self-test (required to enable the stoplamp output driver if DTC B106E is present). TEST the system for normal operation.
If DTC B106F is present, INSTALL a new SJB. REFER to Multifunction Electronic Modules Service and Repair. TEST the system for normal operation.
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H22 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the SJB 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 SJB. REFER to Multifunction Electronic Modules Service and Repair. 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.
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