GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Captiva 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC P0641-P0643, P0651-P0653, or P0697-P0699

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 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
    • The ignition is ON.
    • The DTCs run continuously when the above condition is met.

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
    • DTCs P0641, P0642, P0643, P0651, P0652, P0653, P0697, P0698, and P0699 are Type B DTCs.
    • The ECM commands the TAC system to operate in a Reduced Engine Power mode.

Conditions for Clearing the DTC

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

Diagnostic Aids
    • If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected.
    • The scan tool 5 volt reference parameter should display OK.

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:

    • The accelerator pedal position (APP) sensor 2
    • The fuel rail pressure (FRP) sensor
    • The turbocharger boost pressure sensor

P0697, P0698, P0699

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

    • The air conditioning (A/C) refrigerant pressure sensor
    • The water in fuel sensor
    • The diesel particulate filter (DPF) pressure sensor

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Engine Control Module Connector End Views
    •  Engine Controls 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

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

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.
    3. ⇒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.
    4. ⇒ 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.

    •  Turbocharger Pressure Sensor Replacement
    •  Exhaust Pressure Sensor Replacement
    •  Accelerator Pedal Position Sensor Replacement
    •  Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement
    •  Water in Fuel Indicator Sensor Replacement
    •  Control Module References for ECM replacement, setup, and programming

Repair Verification

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

⇒If greater than the specified range, perform a DPF service regeneration. Refer to Exhaust Particulate Filter Cleaning .