Pinpoint Test K: The Turn Signal Function Is Inoperative

Turn Signal and Hazard Lamps

Pinpoint Test K: The Turn Signal Function Is Inoperative

Refer to Wiring Diagram Set 90, Turn Signal/Stop/Hazard Lamps for schematic and connector information Electrical Diagrams.

Normal Operation

The Body Control Module (BCM) sends voltage signals to the multifunction switch to monitor the LH and RH turn input circuits. The voltage signal is routed to ground when the multifunction switch is placed in the LH or RH TURN position. When the BCM (Body Control Module) detects the multifunction switch is in the LH or RH TURN position, the BCM (Body Control Module) sends voltage to the appropriate turn lamps.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Multifunction switch

- BCM (Body Control Module)

PINPOINT TEST K : THE TURN SIGNAL FUNCTION IS INOPERATIVE

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

K1 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 operate correctly?

Yes
GO to K2.

No
REFER to Headlamps Testing and Inspection.

K2 BYPASS THE MULTIFUNCTION SWITCH

- Ignition OFF.

- Disconnect: Multifunction Switch C202A.

- For an inoperative LH turn signal, connect a fused jumper wire between the multifunction switch C202A-4, circuit CLS39 (VT/WH), harness side and the multifunction switch C202A-9, circuit GD115 (BK/GY), harness side.





- For an inoperative RH turn signal, connect a fused jumper wire between the multifunction switch C202A-8, circuit CLS41 (GY/YE), harness side and the multifunction switch C202A-9, circuit GD115 (BK/GY), 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 K3.

K3 CHECK THE TURN LAMP REQUEST INPUT CIRCUIT FOR AN OPEN

- Disconnect: BCM (Body Control Module) C2280E.

- For an inoperative LH turn signal, measure the resistance between the multifunction switch C202A-4, circuit CLS39 (VT/WH), harness side and the BCM (Body Control Module) C2280E-7, circuit CLS39 (VT/WH), harness side.





- For an inoperative RH turn signal, measure the resistance between the multifunction switch C202A-8, circuit CLS41 (GY/YE), harness side and the BCM (Body Control Module) C2280E-8, circuit CLS41 (GY/YE), harness side.





Is the resistance less than 5 ohms?

Yes
GO to K4.

No
REPAIR circuit CLS39 (VT/WH) (LH turn) or circuit CLS41 (GY/YE) (RH turn) for an open. TEST the system for normal operation.

K4 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.