Pinpoint Test L: The Turn Signal Lamps Are Inoperative

Turn Signal and Hazard Lamps

Pinpoint Tests

Pinpoint Test L: The Turn Signal Lamps Are Inoperative

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

Normal Operation

The Central Junction Box (CJB) fuse 130 (15A) provides voltage to the Generic Electronic Module (GEM) for the turn signal/hazard lamp functions. The GEM sends voltage signals to the multifunction switch to monitor the LH turn input and the RH turn input. When the multifunction switch is placed in the LH or RH TURN position, the voltage signal for that input circuit is routed to ground. When the GEM detects the multifunction switch in the LH or RH TURN position, the GEM sends voltage to the appropriate turn lamps.

This pinpoint test is intended to diagnose the following:

- Fuse
- Wiring, terminals or connectors
- Multifunction switch
- GEM


PINPOINT TEST L: 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.

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L1 CHECK FOR CORRECT HIGH BEAM OPERATION


- Ignition ON.
- 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
If both LH and RH turn lamps are inoperative, GO to L2. If only one side is inoperative, GO to L3.

No
GO to Pinpoint Test B Pinpoint Test B: Both High Beams Are Inoperative.

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L2 CHECK FOR VOLTAGE TO THE GEM


- Ignition OFF.
- Disconnect: GEM C201e.
- Measure the voltage between the GEM C201e-4, circuit 29-LG26 (OG), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to L3.

No
VERIFY the CJB fuse 130 (15A) is OK. If OK, REPAIR circuit 29-LG26 (OG) for an open. TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number

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L3 CHECK FOR A VOLTAGE SIGNAL TO THE MULTIFUNCTION SWITCH


- Connect: GEM C201e.
- Disconnect: Multifunction Switch C202.
- Ignition ON.
- For the LH turn signal, measure the voltage between the multifunction switch C202-6, circuit 49S-LG1 (BU), harness side and ground.




- For the RH turn signal, measure the voltage between the multifunction switch C202-7, circuit 49S-LG18 (BU), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
INSTALL a new multifunction switch. REFER to Steering Column Switches Steering Column Multifunction Switch. TEST the system for normal operation.

No
GO to L4.

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L4 CHECK THE TURN SIGNAL REQUEST INPUT CIRCUIT FOR AN OPEN


- Disconnect: GEM C201b.
- For an inoperative LH turn signal, measure the resistance between the GEM C201b-18, circuit 49S-LG1 (BU), harness side and the multifunction switch C202-6, circuit 49S-LG1 (BU), harness side.




- For an inoperative RH turn signal, measure the resistance between the GEM C201b-17, circuit 49S-LG18 (BU), harness side and the multifunction switch C202-7, circuit 49S-LG18 (BU), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to L5.

No
REPAIR circuit 49S-LG1 (BU) (LH turn signal) or circuit 49S-LG18 (BU) for an open. TEST the system for normal operation.

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L5 CHECK FOR CORRECT GEM OPERATION


- Disconnect all the GEM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the GEM 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 GEM. 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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