Volt

DTC P0641, P0651, P0697, or P06A3 - ECM

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

DTCs P0641, P0651, P0697, and P06A3 run continuously when the ignition voltage is greater than 6.4 V.

The ECM detects a voltage out of tolerance condition on the 5 V reference 1, 2, 3, or 4 circuit for less than 1 s.

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

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

P0641

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

P0651

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

P0697

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

P06A3

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

It may be possible to locate the fault by disconnecting one component at a time from the appropriate 5 V reference circuit while viewing the corresponding 5-volt Reference 1-4 Circuit Status 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.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Hybrid Modes of Operation Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Vehicle in Service Mode, observe the DTC information with a scan tool. DTCs P0641, P0651, P0697, and P06A3 should not set.
2. Observe the circuit status parameters listed below:

•	5 V Reference 1 Circuit Status

•	5 V Reference 2 Circuit Status

•	5 V Reference 3 Circuit Status

•	5 V Reference 4 Circuit Status

Each 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.

Note: Additional DTCs will set when disconnecting components

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

⇒	If less than the specified range, test for a short to ground on the 5 V reference circuit for each of the affected components. If all circuits test normal, replace the K20 ECM.

⇒	If greater than the specified range, test for a short to voltage on the 5 V reference circuit for each of the affected components. 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 5 V reference circuit one at a time while monitoring the appropriate scan tool 5 V Reference 1, 2, 3, or 4 parameter. The voltage should display 4.8-5.2 V.

⇒	If not within the specified range when a component is connected, test the signal circuit of the component for a short to voltage. If the circuit tests normal, replace the component.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.