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For 1990-2009 cars only

DTC B1424 TDM

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 Descriptor

DTC B1424: Device 1 Voltage Low

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

B+

B1424 00

B1424 00

--

--

Ground

--

B1424 00

--

--

Circuit/System Description

The theft deterrent module (TDM) monitors the battery positive (B+) circuit. If the voltage at the TDM is between 6 and 9 V, and the voltage being reported by the serial data message is greater than 9 V, DTC B1424 will set.

Conditions for Running the DTC

    • The Ignition is in Accessory or RUN.
    • The diagnostic runs every 100 milliseconds.

Conditions for Setting the DTC

    • Voltage at the B+ circuit is between 6 and 9 V.
    • Reported battery voltage received via serial data is valid and is greater than 9 V.
    • The above conditions have been met for 2 seconds.

Action Taken When the DTC Sets

    • Security Indicator turns ON.
    • The driver information center (DIC) displays the SERVICE THEFT DETERRENT SYSTEM message.

Conditions for Clearing the DTC

    • A current DTC clears when the battery voltage at the TDM is greater than 9 V, or if the reported voltage by serial data is less than 9V.
    • A history DTC clears after 100 ignition cycles, if no failures are reported by the diagnostic.

Reference Information

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Immobilizer 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

Diagnostic Aids

A low voltage DTC in multiple modules indicates a concern in the charging system.

Circuit/System Verification

  1. Engine running measure and record the voltage at the battery terminals. Verify that the battery voltage is 12.6-15.5 V.
  2. If the battery voltage is not within the specified range, refer to Charging System Test

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the theft deterrent module (TDM).
  2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 Ω between the ground circuit terminal 3 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON , verify a test lamp illuminates between the B+ circuit terminal 1 and ground.
  5. If the test lamp does not illuminate, test the B+ voltage circuit for a short to ground or an open/high resistance.
  6. If the circuits test normal, replace the TDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for TDM replacement, set up, and programming.

DTC B1424 Coolant Heater

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 Descriptor

DTC B1424: Device 1 Voltage Low

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

B+

B1424 00

B1424 00

--

--

Ground

--

B1424 00

--

--

Circuit/System Description

The Heater Coolant Heater Control Module (HCHCM) monitors the system voltage to ensure that the voltage stays within the proper range. Damage to components, and incorrect data may occur when the voltage is out of range.

Conditions for Running the DTC

    • The voltages supplied to the control module is between 9.5-18 V.
    • The ignition is ON.
    • The engine is running.

Conditions for Setting the DTC

HCHCM detects a system voltage below 10.2 V for 15 seconds.

Action Taken When the DTC Sets

The control module immediately disables all outputs when an out of range voltage condition has been detected.

Conditions for Clearing the DTC

The DTC clears when the system voltage returns to a normal range.

Reference Information

Schematic Reference

HVAC Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Air Temperature 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

Diagnostic Aids

A low voltage DTC in multiple modules indicates a concern in the charging system.

Circuit/System Verification

  1. Observe the scan tool Auxiliary Heater Control Module, System Voltage High, System Voltage Low, DTC Set This Ignition parameters will assist you to verify if the fault is present.
  2. Verify that DTC B1424 is set as current.
  3. Engine running measure and record the voltage at the battery terminals.
  4. Verify that the battery voltage is 12.6-15.5 V.
  5. If the battery voltage is not within the specified range, refer to Charging System Test.
  6. Observe the scan tool Auxiliary Heater Control Module ignition signal parameter.
  7. The battery terminal and AHCM parameter should not differ by more than 2 V.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the Heater Coolant Heater Control Module (HCHCM).
  2. Ignition OFF, test for less than 3.0 Ω between the ground circuit terminal H X2 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON , verify a test lamp illuminates between the B+ voltage circuit terminal  A X2 and ground.
  5. If the test lamp does not illuminate, test the B+ voltage circuit for a short to ground or an open/high resistance.
  6. If the circuits test normal, replace the Heater Coolant Heater Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Heater Coolant Heater Control Replacement