Durango 4WD V8-5.9L VIN Z (1998)
Technical Service Bulletin # 24-05-99
Date: 990219
Rear A/C Unit - Blows Warm Air When Hot Outside
NUMBER: 24-05-99
GROUP: Heater & A/C
DATE: Feb. 19, 1999
SUBJECT:
Rear A/C Unit Blows Warm Air When Ambient Temperatures Are High
OVERVIEW:
This bulletin involves installing front and rear expansion valves and in some cases, lowering the headliner and installing front and side/bottom seals to
the rear A/C unit.
MODELS:
1998 - 1999 (DN) Durango
NOTE:
THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH REAR A/C (SALES CODE HBA) BUILT BEFORE DECEMBER 14, 1998
(MDH 1214XX).
SYMPTOM/CONDITION:
The rear A/C unit blows warm air out of the overhead ducts when ambient temperatures are greater than 32°C. (90°F.) with the rear A/C ON and with the
front A/C functioning normally.
NOTE:
THE CONDITION MAY BE WORSE WITH HIGH SUN LOADS APPLIED TO THE ROOF PANEL OF THE VEHICLE.
DIAGNOSIS:
NOTE:
IF THE VEHICLE WAS BUILT BETWEEN OCTOBER 1, 1998 (MDH 1001XX) AND DECEMBER 14, 1998 (MDH 1214XX), PROCEED TO
THE EXPANSION THERMAL VALVE REPAIR PROCEDURE.
1.
Measure the ambient air temperature of the repair area. DO NOT proceed unless the ambient temperature is at least 21°C (70°F).
2.
Connect a tachometer.
3.
Set the heater-A/C mode control switch knob to the MAX A/C position. Set the temperature control knob to the full cool position. Set the blower
motor switch knob of both the front A/C and rear overhead A/C systems to the high speed position.
4.
Start the engine and hold the engine speed at 1,000 rpm with the compressor clutch engaged. Operate the engine until the engine temperature
reaches its normal operating range.
