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P0641

DTC P0641: 5 Volt Reference 1 Circuit

Circuit Description
The Engine Control Module (ECM) provides 5 V to the following sensors through the 5 Volt Reference 1 Circuit:
- Throttle Position (TP) sensor 1, 2
- Accelerator Pedal Position (APP) sensor 1

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 volt reference 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 1 voltage is greater than 5.5 V or less than 4.5 Vfor 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 1-4:




Step 5-10:




Troubleshooting