Clarification Of THERMOPROTECTOR Testing (10-59-90)

Publication date: 1990-07-06
Reference number: 10-59-90

CLARIFICATION OF THERMOPROTECTOR TESTING

TECHNICAL SERVICE BULLETIN

Reference Number(s): 10-59-90, Date of Issue: July 6, 1990
Superceded Bulletin(s): 10-58-90, Date of Issue: 5/30/90

THERMOPROTECTOR TESTING PROCEDURE CLARIFICATION

Model(s): 1991-95 Subaru Legacy

1993-95 Subaru Impreza

Group: 10 - Heating, Ventilation, and A/C System

Bulletin No.: 10-59-90

Date: July 6, 1990

NOTE: This bulletin is to be used as an addendum to Service Bulletin 10-58-90 dated 5/30/90.

APPLICABILITY

All L Series Models with Factory or Accessory Panasonic (Matsushita) Air Conditioning.

THERMOPROTECTOR DIAGNOSIS AND SERVICE PROCEDURE CLARIFICATION

THERMOPROTECTOR FUNCTION (DEFINITION)

The thermoprotector and circuit is designed to open the compressor clutch circuit when the compressor head temperature reaches or exceeds 330°F.

THERMOPROTECTOR'S SERVICE PRECAUTION

Never attempt to service the compressor's thermoprotector without first completely discharging the A/C system. High side pressure is in contact with the thermoprotector's internal surfaces. Removal without discharging the A/C system may cause an extreme safety hazard.

THERMOPROTECTOR TESTING

The thermoprotector circuit must have continuity at temperatures below 330° F. The continuity test can be performed with the A/C system off. See Fig 1 .

Fig 1: Testing Thermoprotector Circuit for Continuity

Locate the thermoprotector connector and disconnect the thermoprotector from the wiring harness.
Using a volt-ohm meter or continuity test light, measure or test for continuity across the two thermoprotector wiring connector terminals.
If the circuit is open or no continuity (ohmmeter shows infinite resistance) the clutch will not engage the A/C system, the thermoprotector must be replaced.

Follow the replacement procedure in Service Bulletin 10-58-90 dated 05-30-90.