DTC P0641, P0651, or P0697
Diagnostic Instructions
DTC Descriptors
DTC P0641 00: 5 V Reference 1 Circuit
DTC P0651 00: 5 V Reference 2 Circuit
DTC P0697 00: 5 V Reference 3 Circuit
Circuit/System Description
The engine control module (ECM) has three 5 V reference circuits. The ECM provides the 5 V reference to various sensors. A short to ground or voltage on one of the 5 V reference circuits will affect all components connected to that 5 V reference circuit. The ECM monitors the voltage on the 5 V reference circuits.
Conditions for Running the DTC
• | The ECM is not commanding reduced engine power. |
• | The ignition voltage is greater than 6 V. |
• | These DTCs run continuously when the above conditions are met. |
Conditions for Setting the DTC
The ECM detects the 5 V reference is out of range for less than 1 s.
Action Taken When the DTC Sets
DTCs P0641 00, P0651 00 and P0697 00 are Type A DTCs.
Conditions for Clearing the DTC
DTCs P0641 00, P0651 00 and P0697 00 are Type A DTCs.
Diagnostic Aids
• | If a shared 5 V reference circuit is shorted to ground or shorted to a voltage, other 5 V reference circuits may be affected. |
• | The scan tool 5 V reference parameter should display between 4.8-5.2 V. |
P0641 00
The 5 V reference 1 circuit provides 5 V to the following sensors:
• | The clutch pedal position switch |
• | The throttle body throttle position sensor 1 and 2 |
• | The accelerator pedal position sensor 1 |
P0651 00
The 5 V reference 2 circuit provides 5 V to the following sensors:
• | The exhaust gas recirculation (EGR) valve |
• | The manifold absolute pressure sensor |
• | The A/C refrigerant pressure sensor |
• | The accelerator pedal position sensor 2 |
P0697 00
The 5 V reference 3 circuit provides 5 V to the following sensors:
The fuel level sensor pin 1
Reference Information
Schematic Reference
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Ignition ON, observe the DTC information with a scan tool. DTCs P0641 00, P0651 00 and P0697 00 should not set.
- Engine idling, observe the following circuit status parameters:
• | 5 V Reference 1 Circuit Status |
• | 5 V Reference 2 Circuit Status |
• | 5 V Reference 3 Circuit Status |
⇒ | Each parameter should display OK. |
- 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 components.
- Ignition OFF, disconnect the harness connector at all appropriate sensors for the applicable DTC. Shown in Diagnostic Aids.
- Ignition ON, test for 4.8-5.2 V between each of the 5 V reference circuits listed below and ground:
• | B25B Clutch Pedal Position Sensor pin C |
• | Q38 Throttle Body pin D |
• | B74 Manifold Absolute Pressure Sensor pin C |
• | B107 Accelerator Pedal Position Sensor pin 1 |
• | B107 Accelerator Pedal Position Sensor pin 2 |
• | Q14 Exhaust Gas Recirculation Valve pin D |
• | B1 A/C Refrigerant Pressure Sensor pin 2 |
• | B46 Fuel Level Sensor pin 1 |
⇒ | If less than the specified range, test for a short to ground on the 5 V reference circuit. If all circuits test normal, replace the K20 Engine Control Module. |
⇒ | If greater than the specified range, test for a short to voltage on the 5 V reference circuit. If all circuits test normal, replace the K20 Engine Control Module. |
Note: A short to voltage on the signal circuit of certain components may cause this DTC to set.
- Connect each component associated with the 5 V reference circuit one at a time while monitoring the scan tool 5 V reference parameter. The voltage should display 5.0 V.
⇒ | If not the specified value, test the signal circuit of the component for a short to voltage. If the circuit tests normal, replace the component. Shown in Diagnostic Aids. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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