Diagnostic Routine S

Diagnostic Routine S

Diagnostic Overview

U012D, U042E

Refer to Wiring Diagram Set 12 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

The charging system supplies voltage to the battery and the vehicle electrical system through the battery B+ cable. The PCM (Powertrain Control Module) monitors the generator output through a dedicated LIN (Local Interconnect Network) communication circuit. The generator uses this LIN (Local Interconnect Network) circuit to communicate the desired voltage setpoint from the PCM (Powertrain Control Module) to the internal voltage regulator. The generator also uses this LIN (Local Interconnect Network) circuit to communicate the generator load and error conditions to the PCM (Powertrain Control Module).

DTC (Diagnostic Trouble Code) Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

- Inspect high current BJB (Battery Junction Box) for loose or corroded connections.

Pinpoint Test

NOTE: Make sure battery voltage is greater than 12.2 volts prior to and during this pinpoint test.

NOTE: Do not have a battery charger attached during vehicle testing.

1. CHECK VEHICLE FOR PRESENCE OF GRILLE SHUTTERS

1. While looking through the grille opening, inspect the vehicle for the presence of grille shutters. REFER to Grille Shutter Assembly .

Is the vehicle equipped with grille shutters?






2. RETRIEVE PCM (Powertrain Control Module) DTCs (Diagnostic Trouble Codes) WITH GRILLE SHUTTER ACTUATOR DISCONNECTED

1. Ignition OFF.

2. Disconnect: Grill Shutter Actuator.

3. Ignition ON.

4. Using a scan tool, perform PCM (Powertrain Control Module) self-test.

Is DTC (Diagnostic Trouble Code) U012D or U042E present?






3. COMPARE THE GENERATOR B+ CIRCUIT TO BATTERY VOLTAGE

1. Measure and record battery voltage.

2. Measure:





Is the voltage within 0.5 volt of the recorded battery voltage?






4. CHECK THE GENERATOR LIN (Local Interconnect Network) CIRCUIT FOR A SHORT TO VOLTAGE

1. Ignition OFF.

2. Disconnect: Generator C102A.

3. Disconnect: PCM (Powertrain Control Module) C175E.

4. Ignition ON.

5. Measure:





Is any voltage present?






5. CHECK THE GENERATOR LIN (Local Interconnect Network) CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

2. Measure:





Is the resistance greater than 10,000 ohms?






6. CHECK THE GENERATOR LIN (Local Interconnect Network) CIRCUIT FOR AN OPEN

1. Measure:









Is the resistance less than 3 ohms?






7. CHECK FOR CORRECT PCM (Powertrain Control Module) OPERATION

1. Ignition OFF.

2. Disconnect and inspect all PCM (Powertrain Control Module) connectors.

3. Repair:

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

4. Reconnect the PCM (Powertrain Control Module) connectors. Make sure they seat and latch correctly.

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

Is the concern still present?