2500 4x4 Pickup V8-360 5.9L VIN 5 Magnum (1994)
Vacuum Harness HVAC: Customer Interest
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.
PARTS REQUIRED:
1
04677204
Check Valve
AR
NPN
Appropriate Size Vacuum Hose
REPAIR PROCEDURE:
This bulletin involves installing an additional vacuum check valve.
