A/C Pressure Sensor Volts Too High

1997 Plymouth Breeze L4-2.0L VIN CSECTION A/C Pressure Sensor Volts Too High
Name of Code:
A/C Pressure Sensor Volts Too High

When Monitored:
With the ignition on, the engine running, and the A/C relay energized,

Set Condition:
The A/C pressure sensor signal at PCM cavity 42 goes above 4.9 volts.

Theory of Operation:
The A/C pressure sensor informs the PCM if the A/C system pressure is too low or too high. This information allows the PCM to determine if it can engage the compressor clutch. If the A/C system pressure is too low, the PCM will not engage the compressor clutch. If the system pressure is too high, the PCM will disengage the compressor clutch and turn on the cooling fans to prevent the compressor head pressure from becoming too high. The sensor provides a signal to PCM cavity 42. The sensor receives a 5-volt supply from PCM cavity 61. The sensor ground is provided by PCM cavity 43.

Possible Causes:
- Sensor signal open
- Sensor internally open
- PCM failure
- Open sensor ground

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.