Pinpoint Test I: The Turn Signal Lamps Are Inoperative
Turn Signal and Hazard Lamps
Pinpoint Test
Pinpoint Test I: 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 SJB provides voltage to the indicator flasher relay when the ignition is in RUN. The indicator flasher relay supplies the voltage to the multifunction switch. When the multifunction switch is placed in the LH or RH TURN position, the multifunction switch routes the voltage to the LH or RH front turn lamps.
The rear turns lamps are combination stop/turn lamps. When the multifunction switch is in the LH or RH turn position, voltage is also routed to the LH or RH rear lamps through the existing stoplamp circuitry.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Indicator flasher relay
- Multifunction switch
- SJB
PINPOINT TEST I: 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.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery.
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I1 CHECK THE TURN SIGNALS
- Ignition ON.
- Place the multifunction switch in the LH and RH TURN positions.
- Do the turn signal lamps illuminate but not flash?
Yes
GO to I2.
No
GO to I4.
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I2 CHECK THE INDICATOR FLASHER RELAY TURN LAMP OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Indicator Flasher Relay C2047.
- Disconnect: Multifunction Switch C202a.
- Ignition ON.
- Measure the voltage between the indicator flasher relay C2047-1, circuit CLS42 (VT/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR circuit CLS42 (VT/BN) for a short to voltage. TEST the system for normal operation.
No
GO to I3.
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I3 CHECK THE MULTIFUNCTION SWITCH FOR A SHORT
- Ignition OFF.
- Carry out the multifunction switch component test.
- Is the multifunction switch OK?
Yes
INSTALL a new indicator flasher relay. TEST the system for normal operation.
No
INSTALL a new multifunction switch. REFER to Steering Column. TEST the system for normal operation.
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I4 CHECK FOR A SHORT TO GROUND
- Listen to the indicator flasher while placing the multifunction switch in the NEUTRAL, LH and RH TURN positions.
- Is there a rapid clicking sound coming from the indicator flasher relay?
Yes
If the sound is continuous regardless of the multifunction switch position, GO to I5.
If the sound is continuous only in the LH or RH TURN position, GO to I7.
No
GO to I8.
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I5 CHECK THE MULTIFUNCTION SWITCH FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Multifunction Switch C202a.
- Ignition ON.
- Is there a rapid clicking sound coming from the indicator flasher relay?
Yes
GO to I6.
No
INSTALL a new multifunction switch. REFER to Steering Column. TEST the system for normal operation.
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I6 CHECK THE INDICATOR FLASHER RELAY TURN LAMP OUTPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Indicator Flasher Relay C2047.
- Measure the resistance between the electronic flasher relay C2047-1, circuit CLS42 (VT/BN), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new indicator flasher relay. TEST the system for normal operation.
No
REPAIR circuit CLS42 (VT/BN) for a short to ground. TEST the system for normal operation.
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I7 CHECK THE TURN SIGNAL LAMP CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Multifunction Switch C202a.
- Disconnect: IC C220a.
- Disconnect: LH or RH Front Turn Lamp.
- Measure the resistance between the multifunction switch C202a-10 (LH turn signal), circuit CLS39 (VT/WH), harness side and ground; or between the multifunction switch C202a-7 (RH turn signal), circuit CLS41 (GY/YE), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new multifunction switch. REFER to Steering Column. TEST the system for normal operation.
No
REPAIR circuit CLS39 (VT/WH) (LH turn signal or circuit CLS41 (GY/YE) (RH turn signal) for a short to ground. TEST the system for normal operation.
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I8 CHECK FOR VOLTAGE TO THE INDICATOR FLASHER RELAY
- Ignition OFF.
- Disconnect: Indicator Flasher Relay C2047.
- Ignition ON.
- Measure the voltage between the indicator flasher relay C2047-5, circuit CBP20 (YE/VT), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to I10.
No
VERIFY the SJB fuse 20 (10A) is OK. If OK, GO to I9. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number
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I9 CHECK THE BATTERY VOLTAGE SUPPLY CIRCUIT TO THE INDICATOR FLASHER RELAY FOR AN OPEN
- Ignition OFF.
- Disconnect: SJB C2280b.
- Measure the resistance between the SJB C2280b-19, circuit CBP20 (YE/VT), harness side and the indicator flasher relay C2047-5, circuit CBP20 (YE/VT), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to I13.
No
REPAIR circuit CBP20 (YE/VT) for an open. TEST the system for normal operation.
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I10 CHECK THE INDICATOR FLASHER RELAY CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the indicator flasher relay C2047-2, circuit GD161 (BK/YE), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to I11.
No
REPAIR circuit GD161 (BK/YE) for an open. TEST the system for normal operation.
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I11 CHECK THE INDICATOR FLASHER RELAY TURN LAMP OUTPUT CIRCUIT FOR AN OPEN
- Disconnect: Multifunction Switch C202b.
- Measure the resistance between the multifunction switch C202b-2, circuit CLS42 (VT/BN), harness side and the indicator flasher relay C2047-1, circuit CLS42 (VT/BN), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to I12.
No
REPAIR circuit CLS42 (VT/BN) for an open. TEST the system for normal operation.
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I12 BYPASS THE MULTIFUNCTION SWITCH
- Connect: Negative Battery Cable.
- Disconnect: Multifunction Switch C202a.
- Connect: Indicator Flasher Relay C2047.
- Connect a fused jumper wire between the multifunction switch C202b-2, circuit CLS42 (VT/BN), harness side and the multifunction switch C202a-10, circuit CLS39 (VT/WH), harness side.
- Ignition ON.
- Does the LH front turn lamp flash?
Yes
REMOVE the jumper wire. INSTALL a new multifunction switch. REFER to Steering Column. TEST the system for normal operation.
No
REMOVE the jumper wire. INSTALL a new indicator flasher relay. TEST the system for normal operation.
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I13 CHECK FOR CORRECT SJB OPERATION
- 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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