Pinpoint Test D: No Power in START
Steering Column Switches
Pinpoint Tests
Pinpoint Test D: No Power in START
Normal Operation
When placed in the START position, the ignition switch provides fused ignition voltage to the PCM and the start diode along circuit CDC35 (BU/WH). The voltage passes through the start diode and continues to the PCM, starter relay and the Smart Junction Box (SJB) along circuit CDC35 (BU/WH).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Ignition switch
- Start diode
- SJB
PINPOINT TEST D: NO POWER IN START
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D1 CHECK THE IGNITION SWITCH
- Carry out the Ignition Switch - Electrical Component Test.
- Does the ignition switch test OK?
Yes
GO to D2.
No
INSPECT the connector for corrosion, pushed-out pins or spread terminals. REPAIR as necessary. If the connector is OK, INSTALL a new ignition switch. REFER to Ignition Switch Ignition Switch. TEST the system for normal operation.
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D2 CHECK THE IGNITION SWITCH START OUTPUT CIRCUIT FOR AN OPEN
- Disconnect: Ignition Switch C250.
- Disconnect: PCM C175B.
- Disconnect: Start Diode.
- Measure the resistance between ignition switch C250-7, circuit CDC35 (BU/WH), harness side and:
- PCM C175B-9, circuit CDC35 (BU/WH), harness side.
- start diode, circuit CDC35 (BU/WH), input side.
- Are the resistances less than 5 ohms?
Yes
GO to D3.
No
REPAIR circuit CDC35 (BU/WH). TEST the system for normal operation.
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D3 CHECK THE IGNITION SWITCH START OUTPUT CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between ignition switch C250-7, circuit CDC35 (BU/WH), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to D4.
No
REPAIR circuit CDC35 (BU/WH). TEST the system for normal operation.
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D4 ISOLATE THE START DIODE
- Test the starter diode.
- Is the starter diode OK?
Yes
GO to D5
No
INSTALL a new diode. TEST the system for normal operation.
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D5 CHECK THE SJB START CIRCUIT FOR AN OPEN
- Disconnect: SJB C2280B.
- Disconnect: Starter Relay.
- Measure the resistance between SJB C2280B-32, circuit CDC35 (BU/WH), harness side and:
- PCM C175B-35, circuit CDC35 (BU/WH), harness side.
- starter diode, circuit CDC35 (BU/WH), output side.
- starter relay, circuit CDC35 (BU/WH).
- Are the resistances less than 5 ohms?
Yes
GO to D6
No
REPAIR circuit CDC35 (BU/WH). TEST the system for normal operation.
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D6 CHECK FOR CORRECT SJB OPERATION
- Check SJB connector C2280B for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: SJB C2280B.
- Make sure the connector seats correctly, then 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. CLEAR the DTCs. REPEAT the self-test.
No
The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.
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