P0697

DTC P0641, P0651, P0697, or P06A3 (ECM, LF1)

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 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

Circuit/System Description

The engine control module (ECM) has 4 internal 5 V reference circuits. Each internal reference circuit provides an external 5 V reference circuit 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

- Ignition voltage is greater than 6.4 V.
- Reduced engine power is not active.
- DTCs P0641, P0651, P0697, P06A3 run continuously when the above conditions are met.

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, and P06A3 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P0641, P0651, P0697, and P06A3 are Type A DTCs.

Diagnostic Aids

P0641
The 5 V reference 1 circuit provides 5 V to the following sensors:

- Fuel tank pressure (FTP) sensor
- Barometric pressure (BARO) sensor, throttle inlet absolute pressure sensor
- Fuel rail pressure (FRP) sensor
- A/C Refrigerant Pressure Sensor
- All four camshaft position sensors

P0651
The 5 V reference 2 circuit provides 5 V to the crankshaft position sensor.

P0697
The 5 V reference 3 circuit provides 5 V to the following sensors:

- Manifold absolute pressure (MAP) sensor
- Accelerator pedal position sensor 2

P06A3
The 5 V reference 4 circuit provides 5 V to the following sensors:

- Throttle position sensor
- Accelerator pedal position sensor 1

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 will change from Malfunction 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 [1][2]Electrical Diagrams

Connector End View Reference
Component Connector End Views

Electrical Information Reference

- Circuit Testing
- Connector Repairs
- Testing for Intermittent Conditions and Poor Connections
- Wiring Repairs

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

Scan Tool Reference
Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, check the diagnostic trouble code (DTC) information with a scan tool. DTC P0641, P0651, P0697, or P06A3 should not set.
2. Observe the scan tool's status parameter for the 5 V reference circuit. 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

1. NOTE: Additional DTCs will set when disconnecting the components.

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.
3. 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.
4. 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.

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

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.

6. If the parameter displays Malfunction 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 after completing the diagnostic procedure.

- Fuel Tank Pressure Sensor Replacement Service and Repair
- Throttle Inlet Absolute Pressure Sensor Replacement (LF1) Service and Repair
- Fuel Pressure Sensor Replacement - Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement - Fuel Injection Fuel Rail
- Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake Camshaft Position Sensor Replacement - Bank 1 (Right Side) Intake
- Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust Camshaft Position Sensor Replacement - Bank 1 (Right Side) Exhaust
- Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake Camshaft Position Sensor Replacement - Bank 2 (Left Side) Intake
- Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust Camshaft Position Sensor Replacement - Bank 2 (Left Side) Exhaust
- Accelerator Pedal with Position Sensor Assembly Replacement Service and Repair
- Throttle Body Assembly Replacement Removal and Replacement
- Crankshaft Position Sensor Replacement Removal and Replacement
- Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement (LF1) Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement (LAU)
- Manifold Absolute Pressure Sensor Replacement (LF1) Service and Repair
- Control Module References for engine control module replacement, setup, and programming