A/C - Delayed Heater Output On Cold Start
Group 64Heating and
Air Conditioning
Bulletin Number
64 05 93 (3750)
Woodcliff Lake, NJ
April 1993
Product Engineering
SUBJECT: Delayed Heater Output
MODELS: E31/E32/E34/E36
Situation:
We have received a few E32/E34 vehicle complaints of reduced temperature heater output, during the first 10-15 minutes of vehicle operation after a cold start in low ambient temperatures.
Cause:
The water valve can stick due to changes to the internal coating. This occurs primarily with the E32/M60, but is also possible with other vehicles.
Correction:
Verify that there are no faults in the IHKA (or IHKR) control module. If no faults are found, and a check of the coolant system reveals no leaks or obvious defects, replace the water valves with new modified parts.
Parts Information:
Improved water valves have a white paint dot next to the date code. Water valve part numbers have not changed. The BMW Parts supply has been purged of the older water valves.
E31/E32/E34 Water Valve (modified) 64 11 1 391 958
E36 Water Valve (modified) 64 11 1 387 319
Warranty Status:
Parts and labor covered under the terms of the applicable BMW New Car Limited Warranty.