P0643 GMC - Sensor Reference Voltage 'A' Circuit High

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
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P0643 GMC Possible Causes

  • Faulty Powertrain Control Module (PCM)
  • Powertrain Control Module (PCM) harness is open or shorted
  • Powertrain Control Module (PCM) circuit poor electrical connection
  • Shorted sensor on 5 volt circuit

First diagnose P0643 GMC code

    Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.

Cost of diagnosing the P0643 GMC code

    Labor: 1.0

    The cost of diagnosing the P0643 GMC code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

When is the P0643 GMC code detected?

The Powertrain Control Module (PCM) has detected the sensor 5 volt reference circuit voltage is higher than expected

P0643 GMC Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P0643 Gmc Description

The Powertrain Control Module (PCM) has 2 internal 5-volt reference buses called
OBDII Code P0643 Gmc - Sensor Reference Voltage 'A' Circuit High - AutoCodes.com

P0643 GMC More Information

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