BMW E32 Modules and Electronics
The E32 is an electrically complex vehicle. When you remove a piece of trim panel chances are that you will discover some sort of control module. Personally I like to know how it all works. So I started looking for all the control modules in the car.
Most of these modules and locations are for my 1987 735. And I'm sure BMW will put some of the control boxes in other locations on other cars.
If any of you are wondering WHY I've taken apart most modules...well it all comes down to because I can and I have to know :)
Servotronic
Usage: The servotronic module controls the variable power steering on the E32.
Location On my car it's located behind the leftside speaker kickpanel.
History: There are at least 2 versions of this modules. The one in the picture and the grey cigarete box.
Images:
IHKA
Usage: The IHKA control module is the brain of the climate control system in the car.
Location: It's located behind the heaterbox. You can reach it by removing the carpet panel on the passengerside of the car.
History There are also at least 2 versions of this module (and more I don't know of). The newer one has different connectors.
Images:
OBC Horn Relay
Usage: This relay controls the OBC gong
Location: It's located on under the rear seat on the leftside. It's bolted to the metal panel in front of the ZKE module carrier.
History: Unknown. Cars with a factory alarm system will have this unit incorperated into the alarm control module (DWA)
Images:
LKM
Usage: The LKM or "Leucht Kontrol Module" controls the lights on the car.
Location: It's located in the fusebox on the leftside under the bonnet.
History/Versions: There are many versions of this module as it is country dependant. And on top of that there are two versions an LKM-B (base model) and an LKM-L (luxus model). The L-version allows the checkcontrol to monitor more bulbs without them having to be on. It also provides the "Lights?" message when you exit the car with the lights on.
Images:
CCM
Usage: The CCM or "Check Control Module" checks all the sensors (and modules as the LKM) to check the status of the washerfluid, oil level, coolant level, oilpressure,...etc
Location: The modules is located under the bonnet in the fusebox on the left.
History: Again there are many versions. Some report "door open?" and others don't
Images:
ZKE
Usage: The ZKE or Zentral Karoserie Elektronic (or central body electronics) consists of 2 modules. A RM or Relay Module and a GM or Gereral Module.
The relay module is just what is says. A module with a collection of relays in it. The GM uses it's TTL signal level to operate power consuming devices such as the electronic window motors.
The general module is the brains of the ZKE. It controls the wipers (and programming there of), the electrical windows and the central locking system and the interiour lighting.
Location: It's located on the left under the rear seats.
History: There are multiple versions of this module. My car seems to have a newer version wich gives some aditional features like one touch windows down on all four windows.
Images:
AUC Control Modle
Usage: This modules tells the IHKA system to go to recirculation mode when the outside air has a too high CO amount (other gases..unsure)
Location: It's located behind the leftside speaker kick panel next to the servotronic module.
History: unknown.
Images:
IR Control Module
Usage: This module controls the infra red remote locking system. The unit has it's own unique code which can be programmed in to the IR remove via the DWA led.
Location: It's located under the rearseat on the left. Right in front of the RM and GM modules.
History: The IR remote locking system was available from 88 to 92.
Images:
Park ventilation Relay
Usage: The parkventilation relaybox controls the park ventilation function that can be programmed through the OBC.
Location: The relay box is located on top of the passengerside glovebox panel.
History: Unknown.
Images:
None yet
Electrical Rear Sunblind
Usage: This module controls the rearsun blind operation
Location: It's located under the rear parcel shelf next to the electronic sunblind.
History: Unknown
Images:
None
Instrument Cluster code plug
Usage: The code plug stores vehicle dependant information such as fuel tank capacity. It also stores the service intervall information and the total milage.
Location: In the older versions it's inside the brown connector of the cable harnass that goes to the instrument cluster. On the newer version from 2/89 it's located in the back of the instrument cluster.
History: There are 3 versions: ->2/89
Images:
Transmission Control Unit
Usage: The TCM controlls the EH automatic gearboxes on the E32
Location: It's located behind the speaker kick panel on the passengerside of the car.
History: There too many version of this module to mention (eg. EGS AGS)
Images:
None yet
Ruck...sperre
Usage: This fancy relay disalows the auto tranny to be switched into reverse while driving.
Location: It's located behind the speaker kick panel on the passengerside of the car under the TCM.
History: Unknown
Images:
None yet
Motronic
Usage: This unit controls the fuel injection of the engine. The R6 and V8 engines have one while the V12 has two of these.
Location: The motronic module is located in the E-box on the right side under the bonnet.
History: Lots of versions.
Images:
None yet
ABS / ASC
Usage: This unit controls the antilocking brakes and anti skid control (where equiped
Location:
History: There are many versions of this unit with and without ASC and ASC+T
Images:
None yet
-> 90
90 ->
Cruise control
Usage:
Location:
History:
Images:
None yet
Airbag Module
Usage:
Location:
History:
Images:
None yet
Siemens vanaf 09-91
EDC Control Module
Usage:
Location:
History:
Images:
None
PDC Control Module
Usage:
Location:
History:
Images:
None
Trailer Module
Usage: This module links the trailer lighting to the check control module.
Location: It's located on the leftside behind the rear carpet trim in the boot of the car.
History: Again many versions available
Images:
None
DWA Module
Usage: This is the brain of the factory anti-theft system.
Location: If you have DWA the module is located in the place of the OBC horn relay
History: There are at least 3 versions of this module: DWA2 (upto 1990) , DWA 3 (1990 to 1992) and DWA 4 (from 09/1992).
Images:
None
If you would like to add any comments, remarks and/or corrections to this procedure, feel free to email Mike Oswald and we'll put it on our site. Share your experiences with us so others may benefit from it.