P06D3 - Sensor Reference Voltage 5 Circuit Low

Theory of Operation

This sensor supply circuit provides a 5-Volt supply to the Accelerator Pedal Position 2 Sensor (APPS), Diesel Particulate Filter Pressure Sensor, Soot Delta Pressure Sensor, and the Transmission Pressure Sensor. The Powertrain Control Module (PCM) illuminates the MIL lamp immediately after the diagnostic runs and fails. The ETC lamp will also flash. During this time the customer will be in a limp home mode. The PCM will turn off the MIL lamp after the diagnostic runs and passes in four consecutive drive cycles.

When Monitored:

With the ignition on, PCM powered.

Set Condition:

Low voltage detected at the 5-Volt Supply circuit.

Possible Causes

APP 2 SENSOR
DIESEL PARTICULATE FILTER PRESSURE SENSOR
SOOT DELTA PRESSURE SENSOR
TRANSMISSION LINE PRESSURE SENSOR (66RFE ONLY)
5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

Diagnostic Test

1. ACTIVE DTC

1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.

4. Turn the ignition off for 75 seconds.
5. Turn the ignition on.
6. With the scan tool, read DTCs.
Did the DTC reset?

Yes
• Go To 2

No
• Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

2. CHECK THE APPS SENSOR 2

1. Ignition on.
2. Disconnect the Accelerator Pedal Position Sensor harness connector.
NOTE: Check connectors - Clean/repair as necessary.
3. Measure the voltage on the (F856) 5-Volt Supply circuit at the Accelerator Pedal Position Sensor harness
connector.
Is the voltage reading between 4.9 and 5.1 Volts?

Yes
• Replace the Accelerator Pedal Position Sensor in accordance with the service information.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No
• Go To 3

3. CHECK THE DIESEL PARTICULATE FILTER PRESSURE SENSOR

1. Disconnect the Diesel Particulate Filter Pressure Sensor harness connector.
NOTE: Check connectors - Clean/repair as necessary.
2. Measure the voltage on the (F856) 5-Volt Supply circuit at the Diesel Particulate Filter Pressure Sensor harness connector.
Is the voltage reading between 4.9 and 5.1 Volts?

Yes
• Replace the Diesel Particulate Filter Pressure Sensor in accordance with the service information.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No
• Go To 4

4. CHECK THE SOOT DELTA PRESSURE SENSOR

1. Disconnect the Soot Delta Pressure Sensor harness connector.
NOTE: Check connectors - Clean/repair as necessary.
2. Measure the voltage on the (F856) 5-Volt Supply circuit at the Soot Delta Pressure Sensor harness connector.
Is the voltage reading between 4.9 and 5.1 Volts?

Yes
• Replace the Soot Delta Pressure Sensor in accordance with the service information.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No
• Go To 5

5. CHECK THE TRANSMISSION LINE PRESSURE SENSOR (66RFE ONLY)

1. Disconnect the Transmission Pressure Sensor harness connector.
NOTE: Check connectors - Clean/repair as necessary.
2. Measure the voltage on the (F856) 5-Volt Supply circuit at the Transmission Pressure Sensor harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes
• Replace the Transmission Line Pressure Sensor in accordance with the service information.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No
• Go To 6

6. CHECK THE (F856) 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND

1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Check connectors - Clean/repair as necessary.
4. Measure the resistance between ground and the (F856) 5-Volt Supply circuit at the Diesel Particulate Filter
Pressure Sensor harness connector.
Is the resistance below 10k Ohms?

Yes
• Repair the (F856) 5-Volt Supply circuit for a short to ground.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No
• Replace and program the Powertrain Control Module in accordance with the service information.
• Perform the POWERTRAIN VERIFICATION TEST - 6.7L. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).