1994 Jaguar XJ6 heater

1994 JAGUAR XJ6
11,800 MILES • 6 CYL • 2WD • AUTOMATIC
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DEEREMAN1969
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  • 1 POST
Yes I am having a problem with my heat on my car, it seems that possibly the blend doors are opening then closing off after 3-4 seconds only allowing cold air to be moved thru out the cars cabin.heater hoses entering the car at the heater core are at operating tempurature. a.c. works as it should any ideas were to locate my problem?
Dec 4, 2009 at 8:16 PM
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DAVE H
  • CAR REPAIR CONTRIBUTOR
  • 13,384 POSTS
INOPERATIVE AUTOMATIC TEMPERATURE CONTROL
Defective in-car sensor. Defective coolant thermostat. Defective CCU. Defective servo control. Defective vacuum actuators. Defective control panel.
SYSTEM SWITCHES MODES DURING ACCELERATION OR UPHILL DRIVING
Vacuum leak in vacuum reservoir tank. Defective vacuum check valve (located near engine, in vacuum supply line). Leaking vacuum hoses. Leaking mode switch.
SYSTEM WILL NOT SWITCH MODES
Vacuum supply loss from engine to firewall connector. Vacuum supply loss from firewall connector to control panel mode switch. Defective CCU. Defective vacuum solenoid. Defective mode switch. Binding linkage or stuck air doors.
Dec 31, 2009 at 7:39 AM
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