1993 Chevrolet Cavalier VL, 4D WagonFACTORY OEM SERVICE PROCEDURE

Diagnostic Aids

In extremely low temperature climate, the A/C pressure signal can drop as low as .3 volt. If this happens, Code 66 will set and disable the A/C system. Clear code and recheck A/C system in a heated garage to determine if outside ambient temperature is cause for Code 66 setting.

Fig 1: Code 66 Schematic (2.2L "L" Body) A/C Pressure Sensor
G93C39430
Factory Service Tools

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When to See a Mechanic

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

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

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