Table of Contents
Variant Coding

Subject

Page

Variant Coding.

Variant Code Identification Display .

Variant Code Structure .

Variant Code Procedure .

Adopt a Variant Code.

Manually Entering a Variant Code

Review Questions.9

Initial Print Date: 12/04

Revision Date:

co ld co h- co

Variant Coding

Model: E24, E28, E30, E32, E34, E36

Production: 3/87-12/95

■biictihis

After completion of this module you will be able to:

• Understand the purpose of variant coding

• Identify control modules/systems that must be variant coded

• Interpret a variant code

• Locate a variant code

• Variant code a control module

2

Variant Coding

Variant Coding

A Variant Code is another means by which market specific application data can be
released/assigned to a control module, this process allows one base control module to be
utilized for different market applications.

The variant code is a 4 digit hexadecimal (alpha-numeric) code that is entered into a con¬
trol module as part of the coding process. By entering a valid code into the module a set
of operational data (characteristic maps) specific to the code entered is assigned to the
operating program of that control module. The operational data and code are semi rigidly
assigned, meaning that if a new code is entered, a different set of data is assigned to the
program.

Variant coding is only used on engine control modules. Engine control modules which
utilize variant coding were first introduced into production vehicles as of 3/87 production
with Motronic M1.1 (Engine Control Module ECM/DME). Refer to TRIB120186 for
more information.

Variant coding is only used on Engine Control Modules with version Ml .X.

DME Version

Series

Cyl.

Engine

Year

Ml .1

E28/E30

6

M20/M30

3/87 - 8/92

Ml.2

E24/E28

6

S38

87-88

Ml.3

E34

6

M20/M30

6/87 - 9/90

Ml.3

E34

6

M30

6/88 -12/92

Ml.3

E32

6

M30

3/87 - 7/92

Ml.7

E30/E36

4

M42

3/90 -12/93

Ml.7.2

E36

4

M42

1/94-12/95

Using the DISplus/GTI/SSS with the latest CIP programming software contained within
Progman, allows the technician to: 0ri 9' nal Replacement

• Code a new, uncoded control module.

• Recode a previously coded control module.

The variant code is entered into the control
module either by:

• Adopting the existing code from the defec¬
tive DME control module (if diagnostic
communication is possible).

• Manually entering the variant code via the
keypad displayed on the screen of the
DISplus/GTI/SSS.

i- i- i- i^i-1

bis m

__ s

o •- _ 5

-b- ^-'

-OR-
Enterthe code

Note: Ml .X DME control modules can only be coded up to eight (8) times. The
GTI/DISplus will display the remaining number of times the control mod¬
ule can be recoded.

3

Variant Coding

If variant coding of an Ml .3 control module for an M20 engine is not possible, Reference
SI B12 06 89 (1878) for more information. The cause may be that Pin 18 (DME Code
Link) of the 20 pin diagnostic connector may be backed out of the connector preventing
communication between the tester and DME control module.

Variant Code Identification Display

The variant code for a DME Ml .X control module can be accessed in three ways:

• Electronically via DISplus or GT1:

- DME Control Module Identification screen

- Select “Programming” then “DME variant code”, installed variant code is dis¬
played.

• DME control module variant code label

• SI B13 02 90 (3009)

The quickest and most accurate way to access the variant code of the installed DME is
by viewing the DME Identification page using the DISplus or GT1.

Print

Change

End

Services

Help

BMW Diagnosis DME IDENTIFICATION

Troubleshooting by means of
perciptible symptoms: "#"

Version: DMEM1.7.2
E30/E36 M42B18

with oxygen-sensor control
EH unledaded Premium

ece/eg/s/ch^w^T

Code 82le -

Bosch Hardware Number: 0261203282
Bosch Software Number: 1267357626
BMW Hardware Number: 1247228

BMW Software Number: 001

Production code: 467

If a control module malfunction is suspected cross reference the BMW and Bosch part
numbers in the display with the installed variant code. Problems can occur if:

• The correct variant code is installed in the wrong control module.

• An incorrect variant code is installed in the correct control module

4

Variant Coding

Variant Code Structure

The four digit structure of the variant code consists of a 16 bit binary code which con¬
verts to a 4 digit hexadecimal code. Each hex character provides information pertaining
to specific functions, characteristic maps and vehicle data.

VARIANT CODE

FUEL TYPE
FUEL OCTANE
X REGULATION

EVAPORITIVE CONTROL
EML REGULATION
ASC CONTROL
STANDARD/VARIANT

MARKET

TRANSMISSION

VEHICLE TYPE
BLANK CHOICE

The information from the variant code is used to define the the operational data to be
assigned to the operating program of the module.

Each hex digit has a binary equivalent that provides four Is or Os which results in a total of
16 bits of information (or choices) per hexadecimal digit.

VARIANT CODE

Under no circumstances should the variant code to be changed from the assigned num¬
ber for the vehicle. Erratic engine operation and possible engine damage may result.

5

Variant Coding

Variant Code Procedure

In the event that an Ml .x control module needs to be replaced or recoded the process
can be accessed through Progman with CIP 15.0 or higher.

To perform the procedure from CIP the Model
series must be selected.

Then select the body (E32, E36 ...)

Select: “Progammierung”

Advance screen to the right two times to enter
the programming/variant coding selection screen.

From the “Selection” screen:

Select: "DME Variant Code"

Select: "Exchange Control Unit"

Select: The Engine version installed on the connected vehicle to be coded Ex. "M40/42/43"

Car Memory
Key Memory
CODIERUNG ZCS/FA

SERVICE MEASURES

PROGRAMMIERUMG

ABGLEICH EWS-DME

ABGLEICH EWS-DDE

The following steps are based on the selection of “M40/42/43”:

"M40/42/43 4-Cyl. has been selected ? Y/N”

Select: “Y”

"Is the vehicle fitted with a DME Ml .7.3 (M43 engine from 9/95) ? Y/N”

Select: “N”

Select: 1 "New Coding"

Select: 1 "Adopt code from old control unit" and follow the procedure indicated once selection is made.
OR

Select: 2 "Enter code manually" (See table for Variant Code) and follow the procedure indicated once
selection is made.

6

Variant Coding

If DME Ml .X control module replacement is required, determine which method of variant
coding you will need.

• Adopt variant code from existing control module

• Manual input of variant code from control module label

Note: For vehicles produced with the M42B19 engine (Ml.7.2 Engine Control
Module) a replacement EPROM was made available for vehicles produced
1/94-12/95 to address a service issue,refer to SIB 12 09 95. Since the
control module for this engine requires a variant code in order to assign
the correct operating data to the program a variant code must still be
assigned to the module upon installing the EPROM.

Adopt a Variant Code

The preferred method of coding a replacement module is by “Adopting” the code from
the old module, since this method prevents accidentally entering the wrong code which
may occur when trying to manually enter the code. If the control module cannot commu¬
nicate on the diagnostic link the manual input method will be necessary (refer to Manually
Entering Variant Code).

The variant code is To

temporarily stored. Workshop

7

Variant Coding

Manually Entering a Variant Code

The process of manually entering a variant code should only be utilized when it is not
possible to communicate with the Engine Control Module (DME) via the DISplus or GT1.
The variant code to be entered can be taken from the label of the problem control mod¬
ule and checked against the listing of variant codes provided in SI B13 02 90 (3009)
prior to entering the code into the new module.

8

Variant Coding

Review Questions

1. What is the purpose of variant coding?

2. What type of control modules need to be variant coded?

3. What type of information does the variant code contain?

4. What happens when a variant code is assigned to a module?

9

Variant Coding