P0651

DTC P0651: 5 Volt Reference 2 Circuit

Circuit Description
The Engine Control Module (ECM) provides 5 voltsto the following sensors through the 5 Volt Reference 2 Circuit:
- Manifold Absolute Pressure (MAP) sensor
- Exhaust Gas Recirculation position sensor
- Accelerator Pedal Position (APP) sensor
- A/C Pressure (ACP) sensor
- Rough Road sensor
- Fuel Tank Pressure (FTP) sensor

A circuit condition on one sensor 5 voltreference circuit may affect the other sensor 5 volt reference circuits. The ECM monitors the voltage on the 5 voltreference circuit. If the ECM detects that the voltage is out of tolerance, a DTC sets.

Conditions for Setting the DTC
- Ignition ON.
- The 5 volt reference 2 voltage is greater than 5.5 V or less than 4.5 V for a certain period of time.

Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will illuminate.
- The ECM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.

Conditions for Clearing the MIL/DTC
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- The DTC(s) can be cleared by using the scan tool.
- Disconnecting the ECM battery feed for more than 10 seconds.

Diagnostic Aids
For an intermittent condition, refer to Intermittents Intermittents.

Step 1-3:

Step 4-10:

Troubleshooting