BMW E32
UNLOCKING THE ON-BOARD-COMPUTER



Section 1; Instrument Cluster OBC display order

We all know that pressing the end of the LHS stalk shows us the OBC information on the Instrument Cluster. But did you know that you can change the order this information is shown and which items are displayed? Well, if you didn't follow the info below:

The shown fields and the order can be adjusted. Use the following mechanism:

Keep the direction switch pressed for about 5 seconds.
You see the Prog 1 indicator in the Speedo display and the OBC
Press the function keys on the OBC in the order you want them to be shown in the Speedo display.
Once a function is in the list, the next press on the same function key results in the second function of that OBC button.
For example: The first time button gives the TIME, the second time button gives the DATE in the Speedo.
Quit the programming function by pressing the direction switch for another short moment.


Check instrument button:
The right hand button on the instrument (speedometer) panel has two special uses:


With the ignition key in Position II (radio and OBC on), pressing this button for about 20 seconds gives the next language. Releasing and pressing again cycles thought the languages (ENGLISH-US, ENGLISH-UK, FRENCH, ITALIANO, ESPANGOL, DEUTCH) with wrap around option.
Note: Not all languages from function 11 can be selected and there are some interactions between setting the language this way and using the OBC function 11. Combination of a DEUTCH language with a LA-J setting in the OBC gives a English-US nationalisation.

Holding the button when turning the ignition key to ON, will perform a LCD lamp test on the instrument panel. This also shows some additional information: BMWNr , CodeNr , K-Zahl , F.G.Nr , SWVersion , AndIndex , LcdTest . The LcdTest does have two steps: First one all meters full (except speedo: 120 km/h, revs: 3500). Second one all meters to "zero" position.

--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x--x

Section 2; OBC 'Hidden' information:

The OBC knows two modes: Locked and Unlocked.
When you get your car, it's probably locked. In the locked mode, the hidden functions will refuse to work.
In the unlocked (free) mode, the hidden functions can be accessed.
Please be carefull to use these functions, especially function 21: This one resets all OBC data !
To change the lock/unlock mode, you have to execute function 19, see the table on this page. Example: On 13 march, you would have to add 13 and 3, giving 16.

The OBC knows two "hidden" keys:


Simultaneously pressing the 100 and 1 displays the car version number. Examples: 7-00 TYP for a 1992, E32, 740IA, Left Hand Drive European.

Simultaneously pressing 1000 and 10 displays "TEST", how these functions are used is described below:


Below is a list of the 'hidden' functions of the OBC.

To select a particular test press '1000' and '10' simultaneously and the OBC will show 'TEST'. You can now select the tests shown below by using the '1' key to enter units and the '10' key to enter 10's of units.....then press the S/R key and the selected test will be displayed. Be warned that test 21 will reset all OBC data and that includes the MPG correction factor (which is usually set to default values anyway):

NOTE: Before simultaneously pressing the 1000 and 10 keys, select a display other than the Time and Date as this will be altered as soon as you press the keys! I usually use 'Temp'.......


Function Display Display Type Explanation Manipulation

1 8888 **** Steady Display Test NONE

2 0.0 V BR Varying Instantaneous fuel consumption in l/100km Measurement

3 0.0 L/H Varying Instantaneous fuel consumption in l/hr Measurement

4 14.0 TVBR Varying Average fuel consumption (used to calc. Range) Calculation from Measurements

5 135 RW Varying Current Range Calculation from Measurements

6 40 T:ADC Varying Amps Measurement

7 35 T:MTL Varying Fuel in tank as a % of full. Measurement

8 70.7 V Varying Instantaneous speed Measurement

9 14.20 uB Varying System voltage at terminal R (where ever that is) Measurement

10 0.97 EICH Setting
Steady ? Speedo meter correction *1 1000/100/10/1 button to change, S/R to save
This doesn't work on my car

11
LA-J
LA-CAN
LA-F
LA-E
LA-I
LA-CH
LA-UK
LA-D
LA-US
LA-FCH Setting Country Setting for language, miles/km, C/F and "l/100Km"/"Km/l" 1000/100 button to change, S/R to save

12 62.9 VANK Varying Average Speed for calc. ETA Calculation from Measurements

13 23.40 ZANK Varying ETA, Estimated time of arrival, provided the required distance is entered ? Calculation from Measurements

14 06.05.1987 89 735I *4
04.04.1990 92 740IA*4
Steady Software Date of OBC NONE

15 92 740IA*4 89 750ILA*4
DIAG Values Values
01 01 C1
02 52 52
03 C3 C3
04 04 A4
05 05 C5
06 06 C6
07 07 E7
08 00 20
09 00 02
Fixed Setting Diagnostic OBC values 1000/100 to up/down DIAG number, no manipulation, no save

16 92 740IA*4 89 750ILA*4 89 735I*4
PORT Values Values Values
01 80/83/87 A0 C1
02 40 05 52
03 1E/5E 00 C3
04 16 1F 0C
05 02/06 46 C5
06 40 D0 C6
07 80 A8 A7
08 04/40/44 7F 70
09 0F 00 00
Varying OBC input port values, depending on engine running or not, etc. 1000/100 to up/down PORT, no save *3

17 92 740IA*4 89 750ILA*4 89 735I*4
PROM Values Values Values
00 D1 9F 64
01 00 00 00
02 00 00 00
03 00 00 00
04 64 64 CA
05 78 64 6E
06 50 42 4C
07 28 24 2D
08 0E 0F 10
09 0C 0E 0F
0A 89 6E C8
0B C7 DE DD
0C DE F1 EE
0D E9 F6 FC
0E 00 01 05
0F 53 61 14
10 C6 C6 CB
11 36 6A 58
12 00 00 00
13 00 00 00
Fixed Setting Vehicle Specific Data, changing between car models NONE

18 HUPEITION
HUPEDTION Setting Horn/Claxon, either single tone or double tone C/F to select, S/R to save

19 LOCK
FREI Setting UNLOCK/LOCK OBC functions,
Add current day and month (as known to OBC) and enter this value 10/1 to set unlock value and S/R to unlock, C/F to lock

NOTE: For instance, if the date was 12th of November, add 12 (the day) to 11 (the month) giving a value of 23; enter this into the OBC using the '1' and '10' keys and then press 'S/R' to unlock, if you need to lock the OBC then press 'C/R' instead.

20 1000 CORR Setting Correction Factor for OBC Fuel Consumption *2 1000/100/10/1 to change, S/R to save

NOTE: On my 730i V8 this is set to 1000 which is the default setting

21 PPPP Action Reset all defect codes, date and time S/R to activate, be carefull !
Selecting this function performs the reset. Note: The "PROM" values won't be reset.


*1
The speedometer in the instrument panel can be calibrated from the OBC. Function 10 is used for this.
Get a stopwatch and search for a flat, deserted highway with km or miles marks. Keep a constant speed of about 60 miles or 100 Km on the speedometer. Measure the time it requires to drive either 2 miles or 2 Km. The actual speed will be:

Actual Speed = Actual Distance (in miles or Km) / Time (in sec) / 0.36

New Correction Value = Old Correction Value * Actual Speed / Speedometer
or
New Correction Value = Old Correction Value * Speedometer / Actual Speed
Please let me know which one, I didn't check.

*2
The average fuel consumption value can be calibrated from the OBC. Function 20 is used for this.
Fill the fuel tank to the maximum. Reset the day trip counter. Run the fuel tank nearly empty and fill the fuel tank again to the maximum. This will give you the fuel consumption.

New Correction Value = Old Correction Value * OBC Fuel consumption (in MPG or l/100Km) / Actual Fuel Consumption (in MPG or l/100Km)
or
New Correction Value = Old Correction Value * OBC Fuel consumption (in MPG or l/100Km) / Actual Fuel Consumption (in MPG or l/100Km)
Please let me know which one, I didn't check.

*3 This value fluctuates between engine off and engine running with different rev's.

*4 Short description Full description
92 740IA "7-00 TYP", 1992, E32, 740IA, Left Hand Drive, Dutch/German Version
89 750ILA "7-01 TYP", 1989, E32, 750ILA, Left Hand Drive, US Version
89 735I "7-05 TYP", 1989, E32, 735I, Right Hand Drive


Functions 15, 16 and 17
Especially the functions 15, 16 and 17 are a bit cloudy at the moment. If enough people are interested, I can try to setup a small database with values related to things like: production date, OBC type, E32/E38, Engine type, transmission type, Left/Right hand drive, Stretched version, seat heaters (front/back) available, alarm, Compartment heaters (time switched by the OBC), luxury package, BMW software upgrade, etc.

 

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