Compressor Clutch Does Not Engage

DIAGNOSTIC AIDS
The mitsubishi scroll type A/C compressor carries an internal thermal cut off switch. The thermal cut off switch normal operation is to open and disable the compressor under extreme load and temperatures above 155°C (311°F). The internal thermal cut off switch is non-serviceable.

TEST DESCRIPTION

Steps 1-5:

Steps 6-18:

Steps 19-31:

Steps 32-42:

The numbers below refer to the step numbers on the diagnostic table.
2. Placing the mode switch in any position other than OFF, along with placing the air temperature control switch in a cold setting, activates A/C operation. For the purpose of this and future steps where A/C operation is necessary, bi-level mode is used for consistent testing.
5. The HVAC control assembly is inoperative when the module does not respond to any operator control requests to enable the A/C compressor. The blower motor may still operate independent of the A/C controls.
11. The A/C compressor relay output is disabled if engine coolant temperature is above 121°C (250°F) for the LX5 and 126°C (259°F) for the L47.

For a description of the RPO Code(s) shown in this article/images refer to the RPO Code List found at Vehicle/Application ID. RPO Codes