A/C - Blows Warm Air

Group Ref.: HVAC

Bulletin No.: 461203

Date: April, 1994

SUBJECT:
AIR CONDITIONER BLOWS WARM AIR (REPLACE A/C DELAY RELAY)

MODELS:
1994 CHEVROLET AND GMC TRUCK S/T PICKUPS WITH 4.3L ENGINE (VIN Z - RPO LB4), 4L60E TRANSMISSION (M30) AND AIR CONDITIONER/MANUAL CONTROLS (C60); OR 4.3L ENGINE (VIN W - RPO L35) AND A/C (C60) BUILT BEFORE THE FOLLOWING VIN BREAKPOINTS:

PLANT DIVISION VIN

LINDEN GMC TRUCK RK501034

SHREVEPORT GMC TRUCK R8501199

SHREVEPORT CHEVROLET R8105893

LINDEN CHEVROLET RK103097

CONDITION:

Some owners may experience a condition where the air conditioner is turned on and delivers only warm air.

CAUSE:

The air conditioner compressor may delay longer than the "original design" intended 12 seconds, or may not engage, due to the possible malfunction of the compressor delay relay.

CORRECTION:

Trucks built before the VIN breakpoints listed above may need a new air conditioner delay relay. Replace only with 15990540 air conditioner compressor delay relay. Specified procedure in Service Manual NATP 9429, Page 1B-59. Test air conditioner operation for delivery of cool air.

NOTE:
To test for proper operation, put the A/C control on the "off" position, start the engine, then place the A/C control in the "on" position. This sequence will provide immediate engagement of the air conditioner compressor. When the engine is started with the A/C control already "on", there will be a normal 15.0 second delay for the air conditioner to engage.

SERVICE PARTS INFORMATION:

P/N Description Qty

1159905401 A/C Compressor Delay Relay 1

Parts are currently available from GMSPO.





WARRANTY INFORMATION:
For vehicles repaired under warranty, use: