For 1990-2009 cars

### 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 B1445 02: Control Module Voltage Output Circuit Short to Ground

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Auxiliary Power Relay Switch B+ | 1 | 1 | 1 | --
Auxiliary Power Relay Control | B1445 02 | 1 | 1 | --
Auxiliary Power Relay Ignition | 1 | 1 | 1 | --
Auxiliary Power Relay Ground | -- | 1 | -- | --
1. Retained Accessory Power Malfunction

### Circuit/System Description

The body control module (BCM) controls the wired accessory power components by applying voltage to the ignition voltage circuit at harness connector X4 terminal 12. Voltage is applied when the ignition switch is in the ACCESSORY or the ON position.

### Conditions for Running the DTC

• | The system voltage is between 9-16 V.

• | The DTC can only set when the output is actively being requested by the module. Refer to Circuit/System Description for specific conditions.

### Conditions for Setting the DTC

The DTC will set only when the module requests the output and there is a short to ground in the ignition voltage circuit.

### Action Taken When the DTC Sets

The module output driver will be shut down and not supply voltage to the circuit.

### Conditions for Clearing the DTC

• | The current DTC will clear when the malfunction is no longer present.

• | A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

### Reference Information

#### Schematic Reference

Power Distribution Schematics

Power Moding Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Retained Accessory Power 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 KR70 auxiliary power relay.
2. Test for less than 10 Ω between the control circuit terminal and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the relay control circuit terminal and ground.
4. Cycle the ignition ON and OFF. The test lamp should turn ON and OFF when changing ignition switch positions.

⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.

⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K9 BCM.

5. If all circuits test normal, test or replace the KR70 auxiliary power relay.

### Component Testing

1. Ignition OFF, disconnect the KR70 auxiliary power relay.
2. Test for 70 - 150 Ω between the B+ terminal and the ground terminal of the KR70 auxiliary power relay.

⇒ | If not within the specified range, replace the KR70 auxiliary power relay.

3. Test for infinite resistance between the following terminals:

• | 30 and 86

• | 30 and 87

• | 30 and 85

• | 85 and 87

⇒ | If not the specified value, replace the KR70 auxiliary power relay.

4. Install a 3 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.

⇒ | If greater than the specified range, replace the KR70 auxiliary power relay.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming