GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2008 🢒 STS 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC B1370

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 B1370 01: Device Ignition Circuit Short to Battery

DTC B1370 02: Device Ignition Circuit Short to Ground

DTC B1370 04: Device Ignition Circuit Open

Circuit/System Description

The remote control door lock receiver (RCDLR) provides a high side drive output for the ignition 1 voltage circuit. The RCDLR controls the Run/Crank relay when the backup power mode is enabled.

Conditions for Running the DTC
    • Voltage supplied to the module is in the normal operating voltage range of 9-16 V.
    • Backup power mode is enabled.

Conditions for Setting the DTC
    • The RCDLR detects a short to ground in the ignition 1 voltage circuit when the output is active.
    • The RCDLR detects a short to voltage or an open in the ignition 1 voltage circuit when the output is inactive.
    • Any of the condition above must be present for more than 0.375 seconds.

Action Taken When the DTC Sets

The RCDLR disables the output for the current ignition cycle when a short to ground is detected.

Conditions for Clearing the DTC
    • A current DTC clears when the malfunction is no longer present.
    • A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Reference Information

Schematic Reference

Power Distribution Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Mode 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 Verification
  1. Ignition OFF, disconnect the IGN 1 relay.
  2. Ignition OFF, Install a 10 A fused jumper wire between the B+ circuit terminal and the control circuit terminal.
  3. Ignition ON, verify DTC B1370 is set.
    4. ⇒If DTC is not set replace the IGN 1 relay.
  4. Ignition OFF, disconnect the X1 harness connector at the IPM and remove the ignition 1 circuit terminal.
  5. Ignition OFF, connect the X1 harness connector at the IPM.
  6. Ignition ON, verify DTC B1370 is set.
    7. ⇒If DTC is not set replace the IPM.
  7. Ignition OFF, disconnect the 10 A fused jumper wire from the IGN 1 relay circuit.
  8. Disconnect the harness connector at the RCDLR.
  9. Test for infinite resistance between the ignition 1 voltage circuit terminal 6 and ground.
    10. ⇒If less than infinite resistance, test the circuit for a short to ground. If the circuit tests normal, replace the RCDLR.
  10. Ignition ON, test for less than 1 V between the ignition 1 voltage circuit terminal 6 and ground.
    11. ⇒If less than infinite resistance, test the circuit for a short to voltage.
  11. If all circuits test normal, replace the RCDLR.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for IPM and RCDLR replacement, programming, and setup