Grand Cherokee 4WD V8-4.7L VIN N (2000)
Vacuum Harness HVAC: All Technical Service Bulletins
Heater A/C System - Defaults To Defrost Mode
NUMBER: 24-24-99
GROUP: Heating & A/C
DATE: Nov. 12, 1999
SUBJECT:
Heater A/C system changes to defrost mode when accelerating
OVERVIEW:
This bulletin involves installing a vacuum check valve in the Heater A/C vacuum supply line.
MODELS:
1999 - 2000 (WJ) Grand Cherokee
NOTE:
THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH MANUAL HEATING & A/C SYSTEMS.
SYMPTOM/CONDITION:
The heater A/C system may default to the defrost mode when accelerating. This will most likely happen in heavy throttle situations such as trailer towing
or accelerating up steep grades.
DIAGNOSIS:
If customers complain of this condition, perform the Repair Procedure.
PARTS REQUIRED:
1
04677204
Check valve
AR
npn
Vacuum hose
REPAIR PROCEDURE:
THIS REPAIR IS COMPATIBLE WITH DAIMLERCHRYSLER'S MOBILE SERVICE PROGRAM AND DOES NOT REQUIRE HOISTS OR
OTHER FULL SERVICE FACILITY SPECIAL EQUIPMENT.