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A/C Heater - Mode Change to Defrost During Acceleration
NO: 24-01-96 Rev. A
GROUP: Heater & A/C
DATE: Oct. 18, 1996
SUBJECT:
Heater
A/C System Changes Mode To Defrost When Accelerating
NOTE
: THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 24-01-96, DATED FEB. 2,
1996, WHICH SHOULD BE REMOVED FROM YOUR FILES. 1997 GRAND CHEROKEE WAS ADDED
TO THE MODEL LIST AND A CLEARER DESCRIPTION OF CHECK VALVE LOCATIONS WERE
ADDED. ALL REVISIONS ARE HIGHLIGHTED WITH **ASTERISKS**.
MODELS:
1993 - **1997** (ZJ) Grand Cherokee
**1996 - 1997** (ZG) Grand Cherokee (International Markets)
1994 - 1996 (BR) Ram Truck
NOTE
: THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH MANUAL A/C
SYMPTOM/CONDITION:
The vacuum supply to the Heater
A/C system may drop when accelerating or when speed control engages. This
may cause the mode vacuum motor to switch to the defrost position.
DIAGNOSIS:
Use the procedure outlined in the appropriate Service Manual (Group 24) to verify that the Heater
A/C system
does not have any vacuum leaks. If no leaks are found, perform the Repair Procedure.