A/C Compressor Clutch - Inoperative
83ford6Article No. 83-22-5
AIR CONDITIONING - CLUTCH INOPERATIVE - UNNECESSARY FIELD COIL REPLACEMENT
FORD 1983-84 ESCORT, EXP, T-BIRD, MUSTANG
LINCOLN-MERCURY 1983-84 LYNX, LN7, COUGAR, CAPRI, CONTINENTAL, MARK VII
LIGHT TRUCKS 1983-84 ECONOLINE
An inoperative A/C compressor clutch may be caused by a diode connected in parallel to the clutch field coil. If the diode is shorted, the symptoms will be the same as a shorted field coil - a blown fuse. To prevent unnecessary replacement of the clutch field coil, use the following test procedure.
FIELD COIL TEST PROCEDURE:
1. Disconnect the wire harness connector from the A/C clutch field coil assembly.
2. Using an ohm meter capable of a low resistance measurement (0-10 ohm) range, set the instrument at a low resistance range and connect the test leads across the two prongs in the field coil connector.
3. The meter should indicate approximately in the interval 2.5 to 4.5 ohm range.
4. Should the meter read substantially lower than the above range and the short condition (indicating a short circuit), the field coil should be replaced.
5. If the resistance value falls within the specified range and the short condition still exists when the harness connector is reconnected, the diode and its wiring harness should be tested for the short condition.
6. Using an ohm meter capable of a high resistance measurement (0-1 million ohm) range, set the instrument on high range and connect the test leads across the terminals of the wire connector. If the resistance falls to zero, reverse the leads at the connector. If the resistance reads high (in excess of 100,000 ohm), the diode is good. If the resistance indicates zero, the diode is shorted.
NOTE: Refer to Shop Manual or Electrical Vacuum Troubleshooting Manual A/C system electrical schematic for diode use and location.
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: "INFORMATION ONLY"