1990 BMW 535iFACTORY OEM SERVICE PROCEDURE

Heating/Air Conditioning Systems (64 10 91 (3417))

Publication date: 1991-11-01
Reference number: 64 10 91 (3417)

HEATING/AIR CONDITIONING SYSTEMS

HEATING/AIR CONDITIONING SYSTEMS

TECHNICAL SERVICE BULLETIN

Reference Number(s): 64 10 91 (3417), Date of Issue:  November, 1991
BMW: 5 Series (E34), 7 Series (E32), 8 Series (E31) - All
GROUP: 64 - Heating and Air Conditioning

SUBJECT

Heating/Air Conditioning Systems

GENERAL INFORMATION

Attached is a survey (up to 9/91 production) of all U.S. variants of IHKA and IHKR Heating/Air Conditioning Systems as found on E31, E32, and E34 vehicles. Each system is identified by designation, software version, and the production period in which it was installed. An illustration of the control panel and a description of equipment and features accompanies each designation.

WARRANTY STATUS

Information only.

ATTACHMENT TO S.I. 64 10 91 (3417)

HEATING AND AIR CONDITIONING SYSTEMS 

E32

IHKA

  1. Designation
    IHKA (without filter)

  2. Control Panel
    See Fig 1 .

  3. Equipment/Features
    10 flap drive motors, 1 Interior temperature sensor in control panel, additional water pump, infinite speed blower, rear seat flap switch/wiring omitted since 06/90, signal is always 'ON' at control unit via the control panel, with Elo connectors since 06/90; with AUC there is a double-function AUC/circulated air button volatile fault memory.

  4. Software Version

    1. 01
      Installed Period: 09/86 - 09/87

    2. 02 small redesign
      Installed Period: 09/87 - 12/88

    3. 03 large redesign
      Installed Period: 12/8 -07/91
IHKAF

  1. Designation
    IHKAF

  2. Control Panel
    See Fig 1 .

  3. Equipment/Features
    Same as IHKA, microfilter between blower final stage and evaporator, volatile fault memory.

  4. Software Version
    03

  5. Installed Period
    06/90 -
Fig 1: E32 Control Panel
G00216763

E31

IHKAF

  1. Designation
    IHKAF

  2. Control Panel
    See Fig 2 .

  3. Equipment/Features
    Overall design same as IHKA (E32), rear seat ventilation omitted, compressor always runs for a certain time after starting; microfilter in air collection box; with AUC there is a double-function AUC/circulated air button volatile fault memory.

  4. Software Version

    1. 04
      Installed Period - 05/90 - 04/91

    2. 05
      Installed Period - 04/91 -
Fig 2: E31 Control Panel
G00216764

E34

IHKR1

  1. Designation
    IHKR1

  2. Control Panel
    See Fig 3 .

  3. Equipment/Features
    1 Interior temperature sensor in control panel, additional water pump, 5 drive motors, defrost + ventilation via cables, arrangement of control unit and blower end stage same as IKHA, push buttons for A/C, circulated air, rear window defogger, volatile fault memory.

  4. Software Version
    00

  5. Installed Period
    06/88 - 01/90
IHKR2

  1. Designation
    IHKR2

  2. Control Panel
    See Fig 3 .

  3. Equipment/Features
    1 Interior temperature sensor in control panel, additional water pump, 3 drive motors for fresh air, circulated air and mixed air, control unit with three 26-pin Elo connectors, blower speed control via resistors, LED buttons for A/C, circulated air, rear window defogger and A/C (air conditioner), non-volatile fault memory.

  4. Software Version

    1. 03
      Installed Period: 01/90 - 04/90

    2. 04 codeable
      Installed Period: 05/90 - 10/90
IHKRF3

  1. Designation
    IHKRF3

  2. Control Panel
    See Fig 3 .

  3. Equipment/Features
    Function and electrical connections same as IHKR2, microfilter in unit in front of evaporator.

  4. Software Version
    04 codeable

  5. Installed Period
    11/90 -
Fig 3: E34 Control Panel
G00216765
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