Diagnostic Routine C

Diagnostic Routine C

Diagnostic Overview

No Power in RUN - Vehicles with an Ignition Switch

Refer to Wiring Diagram Set 13 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

When the ignition switch is turned to the RUN position, a voltage signal is sent to the BCM (Body Control Module). The BCM (Body Control Module) then activates the RUN/START relay and the RUN/ACC relay which distribute fused voltage to various components. The BCM (Body Control Module) uses a FET (Field-Effect Transistor) to control the RUN/START relay. The RUN/START relay receives voltage from BJB (Battery Junction Box) fuse 87 (5A).

The RUN/ACC relay is serviced as part of the BCM (Body Control Module).

DTC Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

Make sure BJB (Battery Junction Box) fuse 87 (5A) is OK.

Pinpoint Test

1. CHECK THE BCM (Body Control Module) FOR DTCs (Diagnostic Trouble Codes)

1. Ignition ON.

2. Using a scan tool, perform BCM (Body Control Module) self-test.

Is DTC (Diagnostic Trouble Code) B1310:14 present?








2. CHECK FOR RUN VOLTAGE AT THE BCM (Body Control Module)

1. Ignition OFF.

2. Disconnect: BCM (Body Control Module) C2280B.

3. Ignition ON.

4. Measure:





Is the voltage greater than 11 volts?








3. CHECK THE IGNITION RUN CIRCUIT FOR AN OPEN

1. Ignition OFF.

2. Disconnect: Ignition Switch.

3. Measure:





Is the resistance less than 3 ohms?








4. CHECK THE RUN/START RELAY

1. Ignition OFF.

2. Remove the RUN/START relay.

3. Carry out the appropriate relay component test.

Is the relay OK?








5. CHECK THE VOLTAGE TO THE RUN/START RELAY COIL

1. Measure:





Is the voltage greater than 11 volts?








6. CHECK THE RUN/START RELAY CONTROL CIRCUIT FOR AN OPEN

1. Ignition OFF.

2. Disconnect: BCM (Body Control Module) C2280F.

3. Measure:





Is the resistance less than 3 ohms?








7. CHECK THE RUN/START RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND

1. Measure:





Is the resistance greater than 10,000 ohms?








8. CHECK FOR CORRECT BCM (Body Control Module) OPERATION

1. Disconnect and inspect all BCM (Body Control Module) connectors.

2. Repair:

- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

3. Reconnect the BCM (Body Control Module) connectors and all previously disconnected exterior system connectors. Make sure they seat and latch correctly.

4. Operate the system and determine if the concern is still present.

Is the concern still present?