Pinpoint Test M: The Turn Signal Lamps Are Inoperative
Turn Signal and Hazard Lamps
Pinpoint Test M: The Turn Signal Lamps Are Inoperative
Refer to Wiring Diagram Set 90, Turn Signal/Stop/Hazard Lamps for schematic and connector information. [1][2]Diagrams By Number
Normal Operation
The Smart Junction Box (SJB) sends voltage signals to the multifunction switch. When the multifunction switch is switched to the LH or RH TURN positions, the voltage signal is switched to ground. When the SJB (Smart Junction Box) detects the multifunction switch in the LH or RH TURN position, the SJB (Smart Junction Box) sends voltage to the appropriate turn lamps.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Multifunction switch
- SJB (Smart Junction Box)
PINPOINT TEST M : THE TURN SIGNAL LAMPS ARE INOPERATIVE
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
M1 CHECK FOR CORRECT HIGH BEAM OPERATION
- Place the headlamp switch in the HEADLAMPS ON position.
- Place the multifunction switch in the HIGH BEAM position while observing the high beam headlamps.
Do the high beams illuminate?
Yes
PLACE the headlamp switch in the OFF position.
For Fusion, GO to M2.
For MKZ, VERIFY the SJB (Smart Junction Box) fuse 6 (20A) is OK. If OK, GO to M3. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. [1][2]Diagrams By Number
No
PLACE the headlamp switch in the OFF position. GO to Pinpoint Test A Pinpoint Test A: Both High Beams Are Inoperative.
M2 CHECK FOR CORRECT STOPLAMP OPERATION
- Apply and release the brake pedal.
Do the stoplamps operate correctly?
Yes
GO to M3.
No
REFER to Stoplamps Special Tool(s) Used With Diagnostics.
M3 BYPASS THE MULTIFUNCTION SWITCH
- Ignition OFF.
- Disconnect: Multifunction Switch C202.
- For an inoperative LH turn signal, connect a fused jumper wire between the multifunction switch C202-2, circuit CLS39 (VT/WH), harness side and the multifunction switch C202-8, circuit GD116 (BK/VT), harness side.
- For an inoperative RH turn signal, connect a fused jumper wire between the multifunction switch C202-3, circuit CLS41 (GY/YE), harness side and the multifunction switch C202-8, circuit GD116 (BK/VT), harness side.
- Ignition ON.
Do the turn signals in question flash on and off?
Yes
REMOVE the jumper wire. INSTALL a new multifunction switch. TEST the system for normal operation.
No
REMOVE the jumper wire. GO to M4.
M4 CHECK THE TURN SIGNAL REQUEST INPUT CIRCUIT FOR AN OPEN
- Disconnect: SJB (Smart Junction Box) C2280B.
- For an inoperative LH turn signal, measure the resistance between the multifunction switch C202-2, circuit CLS39 (VT/WH), harness side and the SJB (Smart Junction Box) C2280B-42, circuit CLS39 (VT/WH), harness side.
- For an inoperative RH turn signal, measure the resistance between the multifunction switch C202-3, circuit CLS41 (GY/YE), harness side and the SJB (Smart Junction Box) C2280B-29, circuit CLS41 (GY/YE), harness side.
Is the resistance less than 5 ohms?
Yes
GO to M5.
No
REPAIR circuit CLS39 (VT/WH) (LH turn signal) or circuit CLS41 (GY/YE) (RH turn signal) for an open. TEST the system for normal operation.
M5 CHECK FOR CORRECT SJB (Smart Junction Box) OPERATION
- 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.