Test Description
WARNING: This page is about a different car, the 1995 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- Checks voltage signal from A/C pressure sensor to PCM. Normal voltage is 0.1-1.8 volts.
- Checks to see if high signal is from a shorted sensor or a short to voltage in circuit. Normally, disconnecting sensor would make a normal circuit go to nearly zero volts.
- Checks to see if low voltage signal is from sensor or circuit. Jumpering sensor signal circuit to 5-volt reference checks circuit, connections and PCM.
- Checks to see if low voltage signal was due to an open in sensor circuit or 5-volt reference circuit. Previous step eliminated pressure sensor as a possible cause.