UPDATE-ELECT. DIAGNOSIS OF C68 ELECT. A/C SYSTEMS

VEHICLES AFFECTED: 1986-88 CORVETTE

1986 Corvette Service Manual Section 8A, page 64-1

Entry into A/C diagnostics requires a C68 A/C control head with a rear defogger button. A substitute A/C Control Head with a Rear Defogger button may be used temporarily when entry into the A/C diagnostic mode is desired.

1987 and 1988 Corvette Service Manual Section 8A, pages 66-1 and 68-2 incorrectly describes entry into the Electronic (C68) A/C diagnostics.

The correct procedure to enter the diagnostics is to press and hold the EXT TEMP button while pressing and then releasing the AUTO button.

For revised electrical diagnosis of C68 Electronic Air Conditioning Systems on 1986, 1987 and 1988 Corvettes substitute the diagnostic procedures with those in the 1989 Corvette Service Manual (ST-364-89). Refer to the electrical schematics for the model year you are working on.

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