Control Units

Here's a useful list which I've put together of control units, the "brains", and their locations.  Part numbers and locations shown are for my UK 1990 GT and may differ for other models and model years. Any info on the unknown control unit is welcomed.


Jetronic fuel computer LH 01 or LH02.  928.618.123.13  On nearside pass. side footwell outer wall in frame with EZ-K unit.


928.618.123.11 is for a 88 S4

928.618.123.12 is for a 88 CS

928.618.123.13 is for a 89/90 S4 (with diag)

928.618.123.14 is for a 89/90 GT

928.618.123.25 is for a 91 auto

928.618.123.26 is for a 91 manual

928.618.123.30 is for a gts

Bosch (928s4)


2. Ignition computer EZ-K 02.  928.618.124.22  On nearside footwell outer wall in frame with LH unit.  
3. Ignition control relay.  928.618.175.00  Clear box above EZ-K unit on the frame.    
4. ABS control unit.   

Large metal box above central electrics fuse/relay board. Bosch Nr. 0 265 106 011

928S4/GT Bj.89 ABS Steuergerät 928.618.118.00, Bosch 0 265 103 039

928S32V/S4/GT ABS Steuergerät Bj. 8/85-7/91 928.618.119.05 Bosch: 0 265 103 035

928S4/GT/GTS ABS Steuergerät 7/91 onwards 928.618.120.01 (including integrated PSD management) located just above the hood opening lever.

5. VDO Lamp controller K1.3.  928.641.603.09  Attached to side of nearside parcel tray. Shown 928.641.603.07  
6. Mirror control unit S4.  928.618.136.01  Black box on offside footwell outer wall.  
7. Hella Alarm unit.  928.637.104.03  Inside dashboard beside glove box. 928.637.104.00 shown

This boxed is replaced by the Porsche Alarm system in 1991

8. Additional Alarm control unit.  928.637.160.00  Blue relay-size box under console behind clock.  
9. Sachs Central locking control unit.  928.618.113.01 Black box under console behind clock. 0r 928.618.125.00  
9A. New alarm unit 928.618.260.00 made by Megamos. Used in 928 from 1991 onwards, and located underneath the right hand seat. It replaces the Alarm units and Warning light unit. Its a processor controlled diagnosis capable controller that handles anti-theft, interior light delay, window control and sunroof, and central locking. Its used in all Porsche '91 vehicles and onwards. It has diag capabilities.  
10. Cruise control unit. 928.617.127.00  Aluminum box fixed to brake pedal bracket behind left hand cover under the instrument panel.

The blue one is the 911.617.227.00 which is used in 928 MY 1987-1995

11. Multi-channel amplifier.  Under carpeted panel by the outside of passenger seat.  
12. RDK control unit (89 s4 and GT)  928 618 150 01

Bosch Nr. 0335563989

There's two versions: RDK00 and RDK02 but these are interchangeable. RDK box is located just below the steering column. RDK was deleted in the 1994 model

13. Control unit for the headlight washer installation 928.618.111.00  
14. Control unit central warning system (1985-1991 models). Behind the footrest. 928.641.602.04  
15. Fan control Unit under the passenger side cover next to the seat. 928.618.418.00  
16. Fan Power stage in front of cooling radiator. 928.005.364.00  
17. Window and Sunroof control unit / regulator  928.618.240.00

This was used in models 1990-1995

18.  Chime Unit 928.618.102.03 located underneath the radio, behind the ashtray  
19. Airbag unit 964.618.217.01 or 964.618.217.04

located behind the center console



20. Wiper relay, in the booth close to the rear wiper.  
22. Seat controller, located under the driver seat. 928 618 134 00  

Hope this is useful to someone. It took me some time locating item 8 for my modification to the central locking system. Much quicker if you know which unit is which. 

Jonathan  (additions by Theo Jenniskens)

1991 Porsche 928 GT