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Home >> Oldsmobile >> 1994 >> Ninety-Eight V6-3800 3.8L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> A/C Signal >> Description and Operation >> A/C Head Pressure Switch
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A/C Head Pressure Switch

A/C Head Pressure Switch Circuit:





Purpose:
The A/C head pressure switch provides the PCM with information regarding A/C high side pressure.

Operation:
The switch opens at 210 psi (1448 kPa) +/- 10. When the head pressure switch interrupts the ground at PCM CKT 380, the left fan should run at high speed.

Location:
The A/C head pressure switch is located in the A/C compressor.
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