Diagnostic Channel 52 - Graphics Channel 1

Diagnostic Channel 52 - Graphics Channel 1

A/C compressor switch-off conditions

Note
If an A/C compressor switch-off condition exists, a segment of the "88-8" display, noted below as an alpha-numeric code, will illuminate.

The conditions listed below are causes of A/C compressor switch-off.

a1 - Slippage or blockage, A/C Refrigerant High Pressure Switch, 120x off

b1 - Engine Speed (RPM) less than 200-500

c1, d1 - Engine Speed (RPM) greater than 6000

e1, f1, *g1 - System function OK

a2 - A/C manually switched off (A/C standby canceled)

b2 - Low voltage

c2 - Kick-down switch (via Transmission Control Module (TCM), compressor off for 12 seconds max.)

d2 - Engine Coolant Temperature (ECT) warning light switch

e2 - A/C Refrigerant Low Pressure Switch (F 73)

f2 - A/C Refrigerant High Pressure Switch (F 118)

*g2 - System function OK

a3 - ECON mode selected

b3 - OFF selected

c3 - Outside (ambient) temperature too low

d3 - Engine management system (compressor will remain off for 3-12 seconds)

e3 - High pressure occurrences more than 30 times

f3 - Ambient Temperature Sensor At Fresh Air Blower (G 109) less than 27°F (-3°C)

*g3 - System function OK

Decimal point visible - A/C compressor ON

Decimal point not visible - A/C compressor OFF

* Segments g1, g2 and g3 must illuminate simultaneously to indicate system function is OK.