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DTC B144C

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    • Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B144C 01: Inverted Run/Start Power Relay Circuit Short to Battery

DTC B144C 06: Inverted Run/Start Power Relay Circuit Low Voltage/Open

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Run Crank Relay B+

B144C 06

B144C 06

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—

Off/Accessory Voltage

B144C 06

B144C 06

B144C 01

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Circuit/System Description

The vehicle theft deterrent subsystem provides the capability to lock or unlock the steering column electrically. The steering column lock control module is allowed to unlock when power mode transitions to a non off power mode and an authenticated driver identification device is present. Once the column is unlocked, a crank request can be allowed.

Conditions for Running the DTC
    • The system voltage is between 9–16 V.
    • The DTC can only run when the steering column lock control module is awake.

Conditions for Setting the DTC

B144C 01

The steering column lock control module detects a short to voltage when the power mode is in the RUN or CRANK for greater than 5 seconds.

B144C 06

The steering column lock control module detects a short to ground or an open in the Off/Accessory circuit when the power mode is in the OFF/ACC for greater than 3 seconds.

Action Taken When the DTC Sets
    • The steering column lock control module will command the driver information centre to display the service column lock warning message.
    • The steering column lock control module indicator is ON.

Conditions for Clearing the DTC
    • The DTC will be current for as long as the fault is present.
    • The DTC will be a history DTC when the voltage is present and the power mode is OFF or ACC or when voltage is not present and the power mode is RUN or CRANK.
    • A history DTC will clear after 50 ignition cycles.

Diagnostic Aids

Verify that DTC B144B is not set prior to performing extensive electrical diagnostics.

Reference Information

Schematic Reference

    •  Column Lock Schematics
    •  Power Moding Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Steering Wheel and Column Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing
  1. Ignition OFF, disconnect the KR73 RUN/CRNK relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87A and ground.
    3. ⇒If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the K60 Steering Column Lock Control Module.
  3. Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  4. Ignition OFF, disconnect the harness connector at the K60 steering column lock control module.
  5. Connect a test lamp between the voltage circuit terminal 3 and ground.
  6. Ignition ON, connect a 5 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87A. Verify the test lamp is illuminated.
    7. ⇒If the test lamp is not illuminated and the control circuit fuse is good, test the control circuit for an open/high resistance.
    ⇒If the test lamp is not illuminated and the control circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, replace the K60 steering column lock control module.
  7. If all circuits test normal, test or replace the KR73 RUN/CRNK relay.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the KR73 RUN/CRNK relay.
  2. Test for 60-200 Ω between terminals 85 and 86.
    3. ⇒If not within the specified range, replace the KR73 RUN/CRNK relay.
  3. Test for infinite resistance between the following terminals:
    4. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    ⇒If not the specified value, replace the KR73 RUN/CRNK relay.
  4. Test for less than 2 Ω between terminals 30 and 87A.
    5. ⇒If greater than the specified range, replace the KR73 RUN/CRNK relay.
  5. Install a 3 A fused jumper wire between the relay terminal 85 and 12 V. Install a jumper wire between the relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.
    6. ⇒If greater than specified range, replace the KR73 RUN/CRNK relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Relay Replacement : Within an Electrical Centre → Attached to Wire Harness
    • Control Module References for the steering column lock control module replacement, setup and programming
   


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