Pinpoint Test L: One Turn Signal/Hazard Lamp Is Inoperative/Always On
Turn Signal and Hazard Lamps
Pinpoint Tests
Pinpoint Test L: One Turn Signal/Hazard Lamp Is Inoperative/Always On
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 or Cutaway Vehicles
When the SJB detects the multifunction switch in the LH TURN position, the SJB provides on/off voltage to the LH front turn lamp.
When the SJB detects the multifunction switch in the RH TURN position, the SJB provides on/off voltage to the RH front turn lamp.
The rear lamps are combination stop/turn lamps that are controlled through the rear stoplamp circuitry.
Stripped Chassis Vehicles
When the SJB detects the multifunction switch in the LH TURN position, the SJB provides on/off voltage to the body builder connector. Ground to the LH front turn lamp is supplied by the body builder.
When the SJB detects the multifunction switch in the RH TURN position, the SJB provides on/off voltage to the body builder connector. Ground to the RH front turn lamp is supplied by the body builder.
The rear lamps are can be combination stop/turn lamps that are controlled through the rear stoplamp circuitry or stand alone turn lamps.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Bulb holder
- Body builder equipment
- SJB
PINPOINT TEST L: ONE TURN SIGNAL/HAZARD LAMP IS INOPERATIVE/ALWAYS ON
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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L1 CHECK THE STOPLAMPS
NOTE: Make sure the SJB self-test has been carried out before continuing diagnostics. Following diagnostic steps before carrying out the self-test can lead to an incorrect repair.
- Ignition OFF.
- Apply and release the brake pedal while observing the stoplamps.
- Do the stoplamps operate correctly?
Yes
GO to L2.
No
REFER to Stoplamps Testing and Inspection.
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L2 DETERMINE IF A TURN LAMP IS ALWAYS ON
- Ignition ON.
- Monitor the turn lamps.
- Is any turn lamp always on?
Yes
GO to L3.
No
For wagon or cutaway vehicles, GO to L5.
For stripped chassis vehicles, GO to L11.
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L3 CHECK THE TURN LAMP VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: SJB C2280f (Front Turn Lamp - Any Vehicle) or C2280c (Rear Turn Lamp - Stripped Chassis) .
- Ignition ON.
- Does the turn lamp in question continue to illuminate?
Yes
For wagon or cutaway vehicles, REPAIR circuit CLS21 (BU/GN) (LH turn lamp) or circuit CLS25 (YE/VT) (RH turn lamp) for a short to voltage. TEST the system for normal operation.
For stripped chassis vehicles, GO to L4.
No
GO to L17.
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L4 ISOLATE THE SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Body Builder C1010 (Front Turn Lamp) or 2026 (Rear Turn Lamp) .
- Ignition ON.
- Does the turn lamp in question continue to illuminate?
Yes
The vehicle is operating correctly. REFER to the body builder manual to continue diagnosis.
No
REPAIR circuit CLS21 (BU/GN) (LH front turn lamp), CLS25 (YE/VT) (RH front turn lamp), CLS23 (GY/OG) (LH rear turn lamp) or CLS27 (GN/OG) (RH rear turn lamp) for a short to voltage. TEST the system for normal operation.
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L5 USE THE RECORDED DTCs FROM THE SJB SELF-TEST (WAGON OR CUTAWAY VEHICLES)
- Check the recorded results from the SJB on-demand self-test.
- Is DTC B2A27 or DTC B2A29 present?
Yes
GO to L6.
No
GO to L9.
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L6 CHECK FOR VOLTAGE TO THE TURN LAMP
- Ignition OFF.
- Disconnect: Inoperative Front Turn Lamp .
- Activate the hazard flasher lamp function.
- Measure the voltage between the LH front turn lamp C1023-3, circuit CLS21 (BU/GN), harness side and ground; or between the RH front turn lamp C1043-3, circuit CLS25 (YE/VT), harness side and ground.
- Does the voltage alternate between 0 and greater than 10 volts?
Yes
GO to L7.
No
GO to L8.
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L7 CHECK FOR VOLTAGE TO THE TURN LAMP USING THE GROUND PIN
- Measure the voltage between the LH front turn lamp C1023-3, circuit CLS21 (BU/GN), harness side and the LH front turn lamp C1023-1, circuit GD129 (BK/YE), harness side; or between the RH front turn lamp C1043-3, circuit CLS25 (YE/VT), harness side and the RH front turn lamp C1043-1, circuit GD131 (BK/GY).
- Does the voltage alternate between 0 and greater than 10 volts?
Yes
INSTALL a new bulb holder. TEST the system for normal operation.
No
REPAIR circuit GD129 (BK/YE) (LH front turn lamp) or circuit GD131 (BK/GY) (RH front turn lamp) for an open. TEST the system for normal operation.
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L8 CHECK THE TURN LAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN (WAGON/CUTAWAY VEHICLES)
- Turn the hazard lamp function off.
- Disconnect: SJB C2280f .
- Measure the resistance between the LH front turn lamp C1023-3, circuit CLS21 (BU/GN), harness side and the SJB C2280f-21, circuit CLS21 (BU/GN), harness side; or between the RH front turn lamp C1043-3, circuit CLS25 (YE/VT), harness side and the SJB C2280f-23, circuit CLS25 (YE/VT), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to L17.
No
REPAIR circuit CLS21 (BU/GN) (LH front turn lamp) or circuit CLS25 (YE/VT) (RH front turn lamp) for an open. TEST the system for normal operation.
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L9 ISOLATE THE BULB HOLDER AS THE CAUSE OF THE CIRCUIT SHORT
- Ignition OFF.
- Disconnect: Inoperative Turn 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 turn lamp output driver if DTC B106E is present).
- Activate the hazard flasher lamp function.
- Measure the voltage between the LH front turn lamp C1023-3, circuit CLS21 (BU/GN), harness side and ground; or between the RH front turn lamp C1043-3, circuit CLS25 (YE/VT), harness side and ground.
- Does the voltage alternate between 0 and greater than 10 volts?
Yes
INSTALL a new bulb holder in question. TEST the system for normal operation.
No
GO to L10.
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L10 CHECK THE TURN LAMP VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: SJB C2280f .
- Measure the resistance between the SJB C2280f-21 (LH front), circuit CLS21 (BU/GN), harness side and ground; or between the SJB C2280f-23 (RH front), circuit CLS25 (YE/VT), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to L17.
No
REPAIR circuit CLS21 (BU/GN) (LH turn lamp) or circuit CLS25 (YE/VT) (RH turn lamp) 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 turn lamp output driver if DTC B106E is present). TEST the system for normal operation.
If DTC B106F is present, INSTALL a new SJB. REFER to Body Control Systems. TEST the system for normal operation.
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L11 CHECK FOR VOLTAGE TO THE BODY BUILDER CONNECTOR
- Ignition OFF.
- Disconnect: Body Builder C1010 (Front Turn Lamp) .
- Disconnect: Body Builder C2026 (Rear Turn Lamp) .
- Activate the hazard flasher lamp function.
- For a front turn lamp, measure the voltage between the body builder C1010-6 (LH front turn lamp), circuit CLS21 (BU/GN), harness side and ground; or between the body builder C1010-5 (RH front turn lamp), circuit CLS25 (YE/VT), harness side and ground.
- For a rear turn lamp, measure the voltage between the body builder C2026-1 (LH rear turn lamp), circuit CLS23 (GY/OG), harness side and ground; or between the body builder C2026-4 (RH rear turn lamp), circuit CLS27 (GN/OG), harness side and ground.
- Does the voltage alternate between 0 and greater than 10 volts?
Yes
The vehicle is operating correctly. REFER to the body builder manual to continue diagnosis.
No
GO to L12.
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L12 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 B2049, B2051, B2A27 or B2A29 present?
Yes
GO to L13.
No
GO to L14.
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L13 CHECK THE TURN LAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Turn the hazard lamp function off.
- Disconnect: SJB C2280f (Front Turn Lamp) .
- Disconnect: SJB C2280c (Rear Turn Lamp) .
- 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 L17.
No
REPAIR circuit CLS21 (BU/GN) (LH front turn lamp), CLS25 (YE/VT) (RH front turn lamp), CLS23 (GY/OG) (LH rear turn lamp) or CLS27 (GN/OG) (RH rear turn lamp) for an open. TEST the system for normal operation.
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L14 ISOLATE THE BODY BUILDER EQUIPMENT AS THE CAUSE OF THE CIRCUIT SHORT
- Turn the hazard lamp function off.
- 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 turn lamp output driver if DTC B106E is present).
- Activate the hazard flasher lamp function.
- For a front turn lamp, measure the voltage between the body builder C1010-6 (LH front turn lamp), circuit CLS21 (BU/GN), harness side and ground; or between the body builder C1010-5 (RH front turn lamp), circuit CLS25 (YE/VT), harness side and ground.
- For a rear turn lamp, measure the voltage between the body builder C2026-1 (LH rear turn lamp), circuit CLS23 (GY/OG), harness side and ground; or between the body builder C2026-4 (RH rear turn lamp), circuit CLS27 (GN/OG), harness side and ground.
- Does the voltage alternate between 0 and 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 L15.
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L15 CHECK THE TURN LAMP VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO GROUND (STRIPPED CHASSIS)
- Ignition OFF.
- Turn the hazard lamp function off.
- Disconnect: SJB C2280f (Front Turn Lamp) .
- Disconnect: SJB C2280c (Rear Turn Lamp) .
- For a front turn lamp, measure the resistance between the SJB C2280f-21 (LH front), circuit CLS21 (BU/GN), harness side and ground; or between the SJB C2280f-23 (RH front), circuit CLS25 (YE/VT), harness side and ground.
- For a rear turn lamp, measure the resistance between the SJB C2280d-21 (LH rear), circuit CLS23 (GY/OG), harness side and ground; or between the SJB C2280d-19 (RH rear), circuit CLS27 (GN/OG), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to L16.
No
REPAIR circuit CLS21 (BU/GN) (LH front turn lamp), circuit CLS25 (YE/VT) (RH front turn lamp), circuit CLS23 (GY/OG) (LH rear turn lamp) or circuit CLS27 (GN/OG) (RH rear turn lamp) for a short to ground. After the repair:
If DTC B106E is present, CLEAR the DTCs and REPEAT the self-test (required to enable the turn lamp output driver if DTC B106E is present). TEST the system for normal operation.
If DTC B106F is present, INSTALL a new SJB. REFER to Body Control Systems. TEST the system for normal operation.
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L16 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 Body Control Systems. TEST the system for normal operation.
No
GO to L17.
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L17 CHECK FOR CORRECT SJB OPERATION
- Ignition OFF.
- 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 Body Control Systems. 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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