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HOMESERVICE MANUALSCHEVROLET2003TRAILBLAZER 4.2 S, 4WDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT VARIANT/TRIMSECTION 2 (ENGINE CONTROL SYSTEM - SELF-DIAGNOSTICS - 5.3L)DIAGNOSTIC TESTSDTC P0641: 5-VOLT REFERENCE CIRCUIT OUT OF RANGEDESCRIPTION
2003 Chevrolet TrailBlazer 4.2 S, 4WD

DTC P0641: 5-Volt Reference Circuit Out Of Range: Description

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Description
WARNING: This page is about a different variant/trim than selected.

The Powertrain Control Module (PCM) provides 5 volts to the following sensors:

  • The Engine Oil Pressure (EOP) sensor.
  • The Manifold Absolute Pressure (MAP) sensor.
  • The engine cooling fan speed sensor.
These 5-volt reference circuits are independent of each other outside the PCM, but are bussed together inside the PCM. Therefore a circuit condition on one sensor 5-volt reference circuit may affect the other sensor 5-volt reference circuits. The PCM monitors the voltage on the 5-volt reference circuit. If the PCM detects that the voltage is out of tolerance, DTC P0641 sets.

RENDER: 1.0x

NO RELATED

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