A/C Compressor - Loading/Low Engine Idle in Defrost Mode
Number: 83-139Section: 1B (Ia)
Date: June, 1984
Subject: A/C COMPRESSOR LOADING IN DEFROST MODE
Model and Year: 1982-83 CELEBRITY, CAVALIER, AND CITATION
TO: ALL CHEVROLET DEALERS
"Please discard previous bulletin 83-T-78, Section 1, issued September, 1983 due to change in part numbers and diagram."
Low engine idle can be caused by high A/C compressor loads due to high head pressures resulting from compressor operation without engine cooling fan operation while in defrost mode.
Engine Cooling Fan Relay:
This condition can be corrected by installing an additional engine cooling fan relay, P/N 14078902 for Celebrity and Citation models or P/N 14073422 for Cavaliers, (see diagram) to operate the engine cooling fan in defrost model. A connector body, P/N 12010015, and terminal ends, P/N 8905087, are available through WDDGM for simplification of the installation of the additional cooling fan relay mentioned in the above article..
The relay should be installed on the cowl, adjacent to the pressure cycling switch. Any wiring run through the cowl should be routed through existing grommets and care be taken to maintain cowl sealing.
WARRANTY INFORMATION
Labor Operation Number: T1094
Labor Time : .4 hours