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 P0652: 5-Volt Reference 2 Circuit Low VoltageDTC P0653: 5-Volt Reference 2 Circuit High Voltage
Diagnostic Fault Information
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
CKP Sensor 5-Volt Reference | P0652, P0335, P2127 | P0335 | P0335 | P0335, P0653, P2128 | -- |
APP Sensor 2 - 5-Volt Reference | P0335, P0652, P2127 | P2138 | P2127 | P0653, P2128 | -- |
Circuit/System Description
The engine control module (ECM) supplies 5 volts to components through 5-volt reference circuits. These 5-volt reference circuits are independent of each other outside the ECM, but are bussed together in three reference groups inside the ECM. Therefore, a circuit condition on one sensor 5-volt reference circuit may affect multiple components. The ECM monitors voltage on the 5-volt reference circuits.
Conditions for Running the DTC
P0652
| • | DTC P0653 is not set. |
| • | The ignition is ON for more than 2 seconds . |
| • | The battery voltage is between 10-16 volts. |
P0653
| • | DTC P0652 is not set. |
| • | The ignition is ON for more than 2 seconds . |
| • | The battery voltage is between 10-16 volts. |
Conditions for Setting the DTC
P0652
The ECM detects the 5-volt reference 2 circuit voltage is less than 4.5 volts.
P0653
The ECM detects the 5-volt reference 2 circuit voltage is more than 5.5 volts.
Action Taken When the DTC Sets
DTC P0652 and P0653 are Type A DTCs.
Conditions for Clearing the MIL/DTC
DTC P0652 and P0653 are Type A DTCs.
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Circuit/System Verification
| • | The engine starts and runs. |
| • | Observe the 5-Volt Reference 2 Circuit Status parameter with a scan tool. The parameter should display OK. |
Circuit/System Testing
- Turn OFF the ignition for 30 seconds or until the ECM powers down.
- Disconnect the accelerator pedal position (APP) sensor.
- Turn ON the ignition, with engine OFF and measure the voltage from the 5-volt reference circuit of the APP sensor 2 to a good ground with a DMM.
- With the DMM still connected to the 5-volt reference circuit, disconnect all other components connected to the 5-volt reference 2, one at a time. Refer to Diagnostic Fault Information.
- Test the 5-volt reference 2 circuits for a short to ground or a short to voltage.
| ⇒ | If the voltage measures 4.7-5.2 volts, replace the APP sensor. |
| ⇒ | If voltage changes when one of the above components is disconnected, replace the component. Refer to the appropriate replacement procedure. |
| ⇒ | If no problem was found in the 5-volt reference 2 circuit , replace the ECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |
