Pinpoint Test O: One Turn Signal/Hazard Lamp Is Inoperative/Always On
Turn Signal and Hazard Lamps
Pinpoint Test O: 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. [1][2]Diagrams By Number
Normal Operation
When the Smart Junction Box (SJB) detects the multifunction switch is in the LH TURN position, the SJB (Smart Junction Box) provides voltage to the LH front turn lamp and LH rear turn lamp. When the SJB (Smart Junction Box) detects the multifunction switch is in the RH TURN position, the SJB (Smart Junction Box) provides voltage to the RH front turn lamp and the RH rear turn lamp.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Bulb holder
- Rear lamp assembly
- SJB (Smart Junction Box)
PINPOINT TEST O : 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.
O1 CHECK THE STOPLAMPS
- Apply and release the brake pedal while observing the stoplamps.
Do the stoplamps operate correctly?
Yes
GO to O2.
No
REFER to Stoplamps Special Tool(s) Used With Diagnostics.
O2 DETERMINE IF A TURN LAMP IS ALWAYS ON
- Ignition ON.
- Monitor the turn lamps while placing the multifunction switch in the RH TURN and then LH TURN positions.
Is any turn lamp always on?
Yes
GO to O3.
No
GO to O4.
O3 CHECK THE SJB (Smart Junction Box) TURN LAMP OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: SJB (Smart Junction Box) C2280F (Front Turn Lamp).
- Disconnect: SJB (Smart Junction Box) C2280C (Rear Turn Lamp).
- Ignition ON.
Does the turn lamp in question continue to illuminate?
Yes
REPAIR circuit CLS21 (BU/GN) (LH front), circuit CLS25 (YE/VT) (RH front), circuit CLS23 (GY/OG) (LH rear) or circuit CLS24 (BN/WH) (RH rear) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to O10.
O4 USE THE RECORDED DTCs FROM THE SJB (Smart Junction Box) SELF-TEST
- Check the recorded results from the SJB (Smart Junction Box) on-demand self-test.
Is DTC B2049, B2051, B2A27 or B2A29 present?
Yes
GO to O5.
No
GO to O8.
O5 CHECK FOR VOLTAGE TO THE TURN LAMP (OPEN DTC PRESENT)
- Ignition OFF.
- Disconnect: Inoperative Turn Lamp.
- Activate the hazard flasher lamp function.
- For a front lamp, 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.
- For an MKZ rear turn lamp, measure the voltage between the LH rear turn lamp C4139-1, circuit CLS23 (GY/OG), harness side and ground; or between the RH front turn lamp C4140-1, circuit CLS24 (BN/WH), harness side and ground.
Does the voltage alternate from 0 volts to greater than 10 volts?
Yes
GO to O6.
No
GO to O7.
O6 CHECK FOR VOLTAGE TO THE FRONT TURN LAMP USING THE CONNECTOR GROUND
- For a front lamp, 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 GD123 (BK/GY), 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 GD121 (BK/YE), harness side.
- For an MKZ rear turn lamp, measure the voltage between the LH rear turn lamp C4139-1, circuit CLS23 (GY/OG), harness side and the LH rear turn lamp C4139-2, circuit GD171 (BK/GY), harness side; or between the RH front turn lamp C4140-1, circuit CLS24 (BN/WH), harness side and the RH front turn lamp C4140-2, circuit GD171 (BK/GY), harness side.
Does the voltage alternate from 0 volts to greater than 10 volts?
Yes
For a front lamp, INSTALL a new bulb holder. TEST the system for normal operation.
For an MKZ rear lamp, INSTALL a new rear lamp assembly. REFER to Rear Lamp Assembly . TEST the system for normal operation.
No
REPAIR circuit GD123 (BK/GY) (LH front), circuit GD121 (BK/YE) (RH front) or circuit GD171 (BK/GY) (LH or RH rear) for an open. TEST the system for normal operation.
O7 CHECK THE SJB (Smart Junction Box) TURN LAMP OUTPUT CIRCUIT FOR AN OPEN
- Turn the hazard lamp function off.
- Disconnect: SJB (Smart Junction Box) C2280F (Front Turn Lamp).
- Disconnect: SJB (Smart Junction Box) C2280C (Rear Turn Lamp).
- For a front lamp, measure the resistance between the LH front turn lamp C1023-3, circuit CLS21 (BU/GN), harness side and the SJB (Smart Junction Box) C2280F-21, circuit CLS21 (BU/GN), harness side; or between the RH front turn lamp C1043-3, circuit CLS21 (BU/GN), harness side and the SJB (Smart Junction Box) C2280F-23, circuit CLS25 (YE/VT), harness side.
- For an MKZ rear turn lamp, measure the voltage between the LH rear turn lamp C4139-1, circuit CLS23 (GY/OG), harness side and the SJB (Smart Junction Box) C2280C-21, circuit CLS23 (GY/OG), harness side; or between the RH front turn lamp C4140-1, circuit CLS24 (BN/WH), harness side and the SJB (Smart Junction Box) C2280C-19, circuit CLS24 (BN/WH), harness side.
Is the resistance less than 5 ohms?
Yes
GO to O10.
No
REPAIR circuit CLS21 (BU/GN) (LH front), circuit CLS25 (YE/VT) (RH front), circuit CLS23 (GY/OG) (LH rear) or circuit CLS24 (BN/WH) (RH rear) for an open. TEST the system for normal operation.
O8 ISOLATE THE BULB HOLDER OR REAR LAMP ASSEMBLY AS THE CAUSE OF THE SHORT TO GROUND
- Ignition OFF.
- Disconnect: Inoperative Turn Lamp.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB (Smart Junction Box) 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 lamp, 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.
- For an MKZ rear turn lamp, measure the voltage between the LH rear turn lamp C4139-1, circuit CLS23 (GY/OG), harness side and ground; or between the RH front turn lamp C4140-1, circuit CLS24 (BN/WH), harness side and ground.
Does the voltage alternate from 0 to greater than 10 volts?
Yes
INSTALL a new bulb holder or rear lamp assembly in question. TEST the system for normal operation.
No
GO to O9.
O9 CHECK THE SJB (Smart Junction Box) TURN LAMP OUTPUT CIRCUIT FOR A SHORT TO GROUND
- Turn the hazard lamp function off.
- Ignition OFF.
- Disconnect: SJB (Smart Junction Box) C2280F (Front Turn Lamp).
- Disconnect: SJB (Smart Junction Box) C2280C (Rear Turn Lamp).
- For a front turn lamp, measure the resistance between the SJB (Smart Junction Box) C2280F-21 (LH turn lamp), circuit CLS21 (BU/GN), harness side and ground; or between the SJB (Smart Junction Box) C2280F-23 (RH turn lamp), circuit CLS25 (YE/VT), harness side and ground.
- For a rear turn lamp, measure the resistance between the SJB (Smart Junction Box) C2280C-21 (LH turn lamp), circuit CLS23 (GY/OG), harness side and ground; or between the SJB (Smart Junction Box) C2280C-19 (RH turn lamp), circuit CLS24 (BN/WH), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to O10.
No
REPAIR circuit CLS21 (BU/GN) (LH front), circuit CLS25 (YE/VT) (RH front), circuit CLS23 (GY/OG) (LH rear) or circuit CLS24 (BN/WH) (RH rear) 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 (Smart Junction Box). TEST the system for normal operation.
O10 CHECK FOR CORRECT SJB (Smart Junction Box) OPERATION
- Ignition OFF.
- Disconnect all the SJB (Smart Junction Box) connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the SJB (Smart Junction Box) 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 (Smart Junction Box). 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. CLEAR the DTCs. REPEAT the self-test.