Diagnostic Instructions

DTC Descriptors

DTC P0641 03: 5-Volt Reference 1 Circuit Below Threshold

DTC P0641 07: 5-Volt Reference 1 Circuit Above Threshold

DTC P0642: 5-Volt Reference 1 Circuit Low Voltage

DTC P0643: 5-Volt Reference 1 Circuit High Voltage

DTC P0651 03: 5-Volt Reference 2 Circuit Below Threshold

DTC P0651 07: 5-Volt Reference 2 Circuit Above Threshold

DTC P0652: 5-Volt Reference 2 Circuit Low Voltage

DTC P0653: 5-Volt Reference 2 Circuit High Voltage

DTC P0697 03: 5-Volt Reference 3 Circuit Below Threshold

DTC P0697 07: 5-Volt Reference 3 Circuit Above Threshold

DTC P0698: 5-Volt Reference 3 Circuit Low Voltage

DTC P0699: 5-Volt Reference 3 Circuit High Voltage

Circuit/System Description

The engine control module (ECM) has 3 5-volt reference circuits. The ECM provides the 5-volt reference to various sensors. Each reference circuit provides a 5-volt reference for greater than one sensor. A short to ground or voltage on one of the 5-volt reference circuits will affect all components connected to that 5-volt reference circuit. The ECM monitors the voltage on the 5-volt reference circuits.

Conditions for Running the DTC

Conditions for Setting the DTC

The control module detects a voltage above 5.5 volts, or below 4.5 volts, on any of the 5-volt reference circuits for greater than 0.5 second.

Action Taken When the DTC Sets

Conditions for Clearing the DTC

DTCs P0641, P0642, P0643, P0651, P0652, P0653, P0697, P0698, and P0699 are Type B DTCs.

Diagnostic Aids

P0641, P0642, P0643

The 5-volt reference 1 circuit provides 5 volts to the accelerator pedal position (APP) sensor 1

P0651, P0652, P0653

The 5-volt reference 2 circuit provides 5 volts to the following sensors:

P0697, P0698, P0699

The 5-volt reference 3 circuit provides 5 volts to the following sensors:

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. DTCs P0641, P0642, P0643, P0651, P0652, P0653, P0697, P0698, and P0699 should not set.
2. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records List.

Circuit/System Testing

Important: 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, measure for 4.6-5.4 volts between one of the 5-volt reference circuits and ground.

⇒	If the voltage is less than the specified value, test for a short to ground on all the 5-volt reference circuits. If all circuits test normal, replace the control module.

⇒	If the voltage is greater than the specified value, test for a short to voltage on all the 5-volt reference circuits for each component associated with the appropriate 5-volt reference circuit. If all circuits test normal, replace the control module.

Important: 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-volt reference circuit one at a time while monitoring the scan tool 5 volt reference parameter. The scan tool parameter should not display Fault.

⇒	If the scan tool displays Fault when a component is connected, test the signal circuit for a short to voltage. If all circuits test normal, replace the component.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Repair Verification

Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 24 grams.