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A/C Pressure Sensor Simulate, 94 Chev. Lumina Sedan

Hi,

My Mom's 94 Chev Lumina (V6 3.1 liter) A/C stopped working. In a process of elimination (see "Test Results" below), I have eliminated some things already. Note: The A/C compressor clutch doesn't engage when A/C is turned on. According to Haynes service manual, this car (3.1 liter engine) doesn't have pressure switches (I couldn't find any).

I removed the connector (3 wires) from the A/C pressure sensor. This sensor symbol in a Haynes service manual looks like a potentiometer with ground on one end, +5V on the other and a wiper arm (pressure). The wires run to the ECM. It is extremely difficult to measure the sensor resistance so I can use a regular "pot" of the same resistance to simulate the pressure sensor.

A Google search did not reveal the information I need.

Do you know any tricks to eliminate the pressure sensor?

Thanks in advance, Brad

TESTS RESULTS:

My cousin brought his A/C pressure gauge and said the pressure was normal (checked on low side) with engine running A/C on "MAX".

I checked the A/C relay in my service shop and checked the "HVAC" fuse (only fuse for AC). I disconnected the connector from the compressor clutch and checked for voltage with engine running and A/C on "MAX". No voltage.

Reply to
Brad
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This may not help, but I did an A/C recharge on my Grandparents '97 Chevy Lumina with the 3.1L V6 a while back. After the system was fully charged, I turned on the A/C, and found the compressor clutch was not on. I looked all over the car for the reason, yet didn't find one. Finally, I realized what I had done. In taking off the air boot (to gain access to the re-fill port for the A/C) I had unplugged 2 sensors. After I plugged those sensors back in, the A/C clutch and the system it self worked perfect. Ice cold.

Like I said, this may not help, but make sure the car is all hooked back up after you are done.

Reply to
80 Knight

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