P06D6

DTC P0641, P0651, P0697, P06A3, P06D2, or P06D6

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptors
DTC P0641
- 5 V Reference 1 Circuit

DTC P0651
- 5 V Reference 2 Circuit

DTC P0697
- 5 V Reference 3 Circuit

DTC P06A3
- 5 V Reference 4 Circuit

DTC P06D2
- 5 V Reference 5 Circuit

Circuit/System Description

The engine control module (ECM) has 5 internal 5 V reference circuits. Each internal reference circuit provides a 5 V reference for more than one sensor. A short to ground or short to voltage on one of the external 5 V reference circuits can affect all the components connected to the same internal 5 V reference circuit.

Conditions for Running the DTC

DTCs P0641, P0651, P0697, P06A3, and P06D2 run continuously when the ignition is ON.

Conditions for Setting the DTC

The 5 V reference circuit voltage is greater or less than a predetermined threshold.

Action Taken When the DTC Sets

DTCs P0641, P0651, P0697, P06A3, and P06D2 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0641, P0651, P0697, P06A3, and P06D2 are Type B DTCs.

Diagnostic Aids

DTC P0641

The 5 V reference 1 circuit provides 5 V to the following sensors:

* Engine oil pressure sensor
* Fuel rail pressure (FRP) sensor
* A/C refrigerant pressure sensor
* Exhaust pressure differential sensor
* Camshaft position sensor

DTC P0651

The 5 V reference 2 circuit provides 5 V to the following sensors:

* Accelerator pedal position (APP) sensor 2
* Manifold absolute pressure (MAP) sensor

DTC P0697

The 5 V reference 3 circuit provides 5 V to the following sensors:

* Intake air flow valve position sensor
* Accelerator pedal position sensor 1

DTC P06A3

The 5 V reference 4 circuit provides 5 V to the exhaust gas recirculation (EGR) position sensor.

DTC P06D2

The 5 V reference 5 circuit provides 5 V to the following sensors:

* Crankshaft position sensor
* Cooling fan speed sensor
* Diesel exhaust fluid pressure sensor
* Turbocharger vane position sensor

It may be possible to locate the fault by disconnecting one component at a time from the 5 V reference circuit while viewing the 5 V Reference Circuit parameter on the scan tool. The scan tool parameter would change from Fault to OK when the source of the fault is disconnected.

If all 5 V reference components have been disconnected and a Fault is still indicated, the fault may exist in the wiring harness.

Reference Information
Schematic Reference

Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. DTC P0641, P0651, P0697, P06A3, or P06D2 should not set.
2. Observe the appropriate scan tool 5 V Reference Circuit Test Status parameter. The parameter should display OK.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Note: Additional DTCs will set when disconnecting the components.

1. Ignition OFF, disconnect the harness connector of all appropriate sensors for the applicable DTC. Refer to Diagnostic Aids.
2. Ignition ON, test for 4.8-5.2 V between one of the affected 5 V reference circuits and ground.

• If the voltage is less than the specified range, test for a short to ground on the 5 V reference circuit for each affected component. If all circuits test normal, replace the K20 ECM.
• If the voltage is greater than the specified range, test for a short to voltage on the 5 V reference circuit for each affected component. If all circuits test normal, replace the K20 ECM.

Note: A short to voltage on the signal circuit of certain components may cause this DTC to set.

3. Connect each component associated with the affected 5 V reference circuit, one at a time, while monitoring the appropriate scan tool 5 V Reference Circuit Status parameter. The parameter should continue to display OK.

• If the parameter displays Fault when a component is connected, test the signal circuit of that component for a short to voltage. If the circuit tests normal, replace the component.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Accelerator Pedal Position Sensor Replacement (Service and Repair)
* Air Conditioning (A/C) High Pressure Switch Replacement (Air Conditioning (A/C) High Pressure Switch Replacement)
* Camshaft Position Sensor Replacement (Service and Repair)
* Crankshaft Position Sensor Replacement (Crankshaft Position Sensor Replacement)
* Emission Reduction Fluid Tank Replacement (Emission Reduction Fluid Tank Replacement)
* Engine Oil Pressure Sensor and/or Switch Replacement (Service and Repair)
* Exhaust Gas Recirculation Valve Replacement (Exhaust Gas Recirculation Valve Replacement)
* Exhaust Pressure Differential Sensor Replacement (Exhaust Pressure Differential Sensor Replacement)
* Fan Clutch Replacement (Service and Repair)
* Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement (Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement)
* Intake Air Valve Replacement (Service and Repair)
* Manifold Absolute Pressure Sensor Replacement (Service and Repair)
* Turbocharger Vane Position Sensor Replacement (Turbocharger Vane Position Sensor Replacement)
* Control Module References (Programming and Relearning) for engine control module replacement, setup, and programming