BMW E36 Blog

Unlock the check button functionality for BMW E36 On Board Computer (OBC)

29th October 2007

Unlock the check button functionality for BMW E36 On Board Computer (OBC)

posted in Technical Info, Tips & Tricks |

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Hi Guys, One of the issues that were annoying me about my car is the OBC (On Board Computer) check button. Whenever I press that button, I was receiving this row of orange squares that I didn’t know what they meant. After a while, I thought this meant the car was ok and that there’s nothing wrong to report until today when I found an article that’s talking about this exact problem and how to unlock the check functionality. It turned out that the row of orange boxes (which looks like a full battery) meant that the check functionality is disabled in the car and that you have to enable it simply by following some easy steps.

Disclaimer: Use this info at your own risk!! I’m not responsible if this didn’t work for you :-).

To unlock your car’s check button functionality:

1. Hold down 1000 and 10 to get access to the hidden menus. [TEST –]

Note: please notice that this may not work if you didn’t unlock the hidden menus in your OBC using TEST 19. If you don’t know how to do this, please refer to my previous post BMW On Board Computer (OBD) secrets!.

2. Enter 11, and press Set/Reset. You will notice this on the OBC screen [EINHEIT 1: xx] (xx will be a number)
3. Change this EINHEIT 1 value to 71, using the 10 and 1 buttons, then press Set/Reset.
4. Press the 1000 button once to move to the next value which is [EINHEIT 2 xx] (xx will be a number)
5. Change this EINHEIT 2 value to FF, using the 10 and 1 buttons, then press Set/Reset.

Note: I’ve found that this value was already set correctly on my OBC.

6. After that, just press your "check" button.

I’ve tried this on my car and I have to admit it didn’t work completely as expected. Now, I receive this "Check Control Inactive" error which apparently trying to tell me that I’m one step short from making this work on my car.

Video of my car OBC after unlocking check functionality

So, if anyone can help with this, please let me know.

If your car is:
325i 1994 or 318is 1993: Set EINHEIT 1 value to 71
320i 1994: Set EINHEIT 1 value to 7B
328i 1995: Set EINHEIT 1 value to BA
M3 1997,1998: Set EINHEIT 1 value to B3

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There are currently 79 responses to “Unlock the check button functionality for BMW E36 On Board Computer (OBC)”

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  1. 1 On September 29th, 2008, Timo Heiskala said:

    Hi guys!

    I did a conversion to fit a 18-button OBC on my 97´ 328i (i had the 12-button one with Check Control working as intended).
    I had the problem with Check button displaying the full orange screen, but setting EINHEIT 1 to BA It started working instantly.
    (Says: Check Control Ok)

    The value for EINHEIT 1 i took from the original post up there that says 328 95 BA.

    Thanks for the post, really helped me out since i had looked for answers to this for quite a long time.

    -Timo Heiskala, Finland

  2. 2 On October 1st, 2008, Jet said:

    I began trying all the possible combinations to get my check control working. So far i tried All the possible combinations on Einheit 1 set to xx and einheit 2 to FF. Didn’t work, so i guess my einheit 2 value must be some other than FF. The best would be if someone with 92 325i 18 button OBC could unlock secret OBC functions and look at their einheit values while the check control is working and write them here 🙂

  3. 3 On October 1st, 2008, ukfrog said:

    Read this thread, enough of us have posted our Ref. for Einheit 1 and 2 up here, just make a little effort and read some of the postings up here. It would be pointless for us to post anything if it’s never read by anyone else than the last couple of visitors.

  4. 4 On October 2nd, 2008, Jet said:

    @ukfrog: what makes you think i haven’t read all the posts? I did, but it didn’t help, these values won’t work for me, so i asked for someone to post it…

  5. 5 On October 2nd, 2008, Ukfrog said:

    Even if you had someone out there with the same year + model as you, the Einheit settings wouldn’t be the same.
    It seems that BMW tech team outdid themselves here, because the OCB is linked to the ECU it seems and is paired with it. This means that the model of the ECU and CHIP is more important than the model of your car.
    ECU come in many models siemens or bosch, then the chip comes in many, many variations.
    So info from 3rd party is not helpful in your case. But you know that don’t you, because you read all the posts in this thread, didn’t you?! he! he!
    All you have left to do is try all the combinations out. LOL
    It shouldn’t take you more than a week end to figure it out, that’s if yours works, unlike Tony’s…

  6. 6 On October 2nd, 2008, Jet said:

    Yes, i’ve read that tony tried all the possible combinations.. and still asked that, because it’s just that some people on other forumus enabled the check functionality by asking for einheit values of the same year and model. Of course, it’s not logical, but this was just my best shot.. I think today i’m gonna writedown TEST15, TEST16 and someother test, which shows the ROM date of the OBC (???). Ukfrog, my obc doesn’t have the value of test 15 you wrote down here, the same number has different values… so i’m very confused. All i know is, that my car light sensors for the obc to tell if the light isn’t working, fluid level indicators and so on… so it must be with check control module..

  7. 7 On October 25th, 2008, Vlakci said:

    hello (please don’t judge my english I am from Slovenia EU)

    I read a lot about this OBC problems regarding fault Check control and fault fuel Consumption.
    I instaled a 18button OBC in my 320iC E36 1/97 because i found the 7button discusting with the
    smole display and low functions. Regarding the problem I spoke with a lot of BMW fanatics (many
    mecchanics in slovenia or germany/austria) and they all told me the same staff:

    – All OBC are the same. If you chech the ETK code are all the same, they change only by language
    of buttons (the can by changed from other units to units – mine is Italian beacuse the car is too).
    If you buy a NEW one from the factory it comes uncoded (the same for ALL models, apart the language
    of the buttons) and you have to code it (it is done by the RDX and TDX data line conected to all
    digital modules of the car (EWS, DWA, OBC,…))
    – The OBC check control works by getting data from the Check control module (above the left speaker above the foot)
    and it is conected to the OBC by 5 wires. The are al digital (1 and 0) and it reads al the fault code
    (lights front, lights back, water level, colant level…)
    – If you change a OBC whitch is NOT from the exact car (year, macchine) you have to coded it
    – the coding is done by the BMW repair shop (by us it cost about 20euro or 25$)
    – If your check controlo reads error is because is not in sincronyse with the check module or the data
    lines are not conected (my didn’t have CC but is working apart the CC reading – it displays the orange
    squares on the holl display with the Check button

    That is the part that the mecchanics told me, I am waiting to get an answer for my email. I the future
    (on april with the opening of the sezone I will doo the coding + ne remote key and all module reset,
    because I have a problem with the sincronyzation of the DWA and ZKE)

    But I have a question: until I do the coding I vill must look to the 2x times to low fuel rate. The calibration allows
    only from 0.75 to 1.25, so I am gessing that the problem is because the OBC is from a 318i 1993. Does any one have
    the codes of EINHEIT1 and 2 for a 1997 convertible M52B20 (or it would be the best that al with the OBC functioning would check the code (2min of work) and write them down with the engine tipe (because of the vanos), and model year (it would be wery help full and
    maybe we can solve the problem for all

  8. 8 On October 25th, 2008, Vlakci said:

    and the test code 14, 15, 16 is only read-only (for the 17 I’m not sure beacause, I forgot what they told me –
    too much information by drinking the coffe)

    By the way : the all upgrade from 7 to 18 button OBC took me 2h writing the electrical diagram, to be sure for all the conections
    (my is connected to A/C, EWS + the instrument cluster) to be wright, 1h to instal, and I made all cables like that, that they look like
    original instaled. The only thing that remains to do is to instal the triger switch by the steering wheel witch
    I get in Monday

  9. 9 On October 25th, 2008, ukfrog said:

    Good work lad!

  10. 10 On October 25th, 2008, Vlakci said:

    hy; me again

    by reading the post I made a little table for the working codes:
    Car – year – einheit1/2 – if cc mentioned/instaled
    318i ? 04 FF yes the cables were on the conector (donor car with CC).with
    the same code squares: on the display (CC in the car not instaled) on a 320i 97′ conv.
    318is 97 04 FF not mentioned
    325i 93 01 FF not mentioned
    325i 93 73 FF check control functional
    325i 93 73 FF not mentioned
    325i 93 01 FF chech control functional
    328i 97 BA FF chech control functional
    328i 95 01 FF check control functional

    To see if you have CC the easyest way is to loke on the fluid container of the windsheild water.
    On the side should be a switch for the water level. Or to remove the cover above the legs, and
    to check for the CC module above the speaker (two conectors black and white, round pins).
    E36 does not have the CC optional as on the 6cly. E30!

    With the modules in E36 is always important the instal electronics with the battery disconected, and
    most importand: first unplug the negative pole of the battery! last plug back the negative pole!

    With what I read I came up with and idea what should be the understanding of the OBC and CC: with the correct code
    the check works if the CC module is conected and functional. If not conected, the OBC by it self does
    the orange squares because it doesn’t have any signal from the CC and it is programed to the sqeares. When you
    change the einheit code (1 or 2 for now no idea) you only scramble the OBC and the conections from the CC
    (or not if no CC in car) doesn’t get to the procesor of the OBC resulting in: error mode, please consult manual etc.

  11. 11 On October 25th, 2008, Vlakci said:

    plus the codes from the original article above:

    325i 1994: 71 FF – for this I think is incorect!
    318is 1993: 71 FF – for this I think is incorect!
    320i 1994: 7B FF
    328i 1995: BA FF
    M3 1997: B3 FF
    M3 1998: B3 FF

  12. 12 On October 26th, 2008, Tony Sticks said:

    @Vlakci: Hmmm… I don’t have the sensor on the windshield fluid reservoir. Maybe I don’t have the check control module and that’s why I keep getting this error. I need to look for the CM and see if it’s there or not. Thank you very much. You’ve been of great help.

  13. 13 On October 26th, 2008, Vlakci said:

    hy. was in the car +, tryed all the cide and:
    only wuth the 04 does the orange squares on the display. All the other codes
    from the table above did chech inactive. So I am assuming that the 04 is for
    non CC instaled E36 with OBC. The other thing I saw is that with the code 01
    the units go to USA, with the other are EU.

    And the codes didn’t solve the problem of the fuel rate factor. Is off by the
    factor 2 as before. So I will take my OBC to a servise for coding beacuse i
    am tired if seeing the wrong feul rate.

  14. 14 On October 26th, 2008, Vlakci said:

    I must correct my self:
    318i ? 04 FF yes the cables were on the conector (donor car with CC)

    the car was not with CC, as told me the seler of the OBC I have bought. He gave me the
    connector with the wires from an other OBC witch had the CC but the display of OBC was

  15. 15 On October 28th, 2008, vlakci said:

    received email from the UK website for customer suport and: please visit your local BMW service. Thanks a lot ?!#$”%&%$”ck. The local service would put the car in prafactors and the most common excuse is: that part doesn’t exist or that car didn’t have that equipment (when I was buying light wipers for my E30 light cleaning sistem).

  16. 16 On November 18th, 2008, Yudh said:

    hey what about 96 323i sedan?

  17. 17 On November 30th, 2008, Robert said:

    I have a ’92 E36 325i with Check Control, and did the 18 button swap, and too am having the Check Control now inactive. At least there is a place here where we can hash out ideas to solve this. Thank you all for your ideas and suggestions. If I had any, I would gladly post them here.

  18. 18 On November 30th, 2008, Robert said:

    I wonder if a “Reset” of the OBC would cause the OBC to find the codes it needs on its own?

  19. 19 On December 2nd, 2008, ukfrog said:

    @ vlakci
    It looks like, on the contrary to all of us, you are not going to give up on this issue before it is solved. My hat off to you mate, I’ve long given up on trying to understand the OCB functions on the E36, but maybe I’ve given up because my 18 button works fine.
    however, I tried for 6 months or so to work out all the functions and their actions, but gave up after frustration took the better of me. Not even BMW Tech seem to know what does what on the OCB settings.
    So my friend, if one day you crack the MYSTERIES of the BMW E36 OBC, I think they should but you in Who’s Who!
    Keep it up, and brake a leg, as they say! (not really brake your leg mate I really wish you all the luck in the world, you going to need it…) LOL

  20. 20 On December 17th, 2008, vlakci said:

    hy; back again.

    The master reset in the secrets menu will not solve the problem.

    For my the thing is solved and I am doing other stuff on my E36 (the multifuncion steering wheel is finish as the electric seats with heating, the business radio too, now i am doing the Mp3 Cd bmw changer and if I am lucky finding the parts the bluetooth sistem for the phone), because I reprogramed my OBC to a newer software and all is working as it should.

  21. 21 On December 23rd, 2008, Mark said:

    Does anyone know if E36 18 button OBC can display oil press and water temperature and how to make this display?

  22. 22 On December 24th, 2008, Tony Sticks said:

    Have you read the BMW On Board Computer (OBC) secrets! post. I think you’ll find a way to read the engine temperature. I don’t know about Oil pressure. Just search there for “Engine temp”

  23. 23 On January 13th, 2009, edupnt said:

    hi. I’ve a 318i, and I’m about to buy a OBC to my car…
    but i still don’t know if it works on my car?
    can anyone help me telling me any thing about it…

  24. 24 On January 14th, 2009, Mark said:

    you are mentioning multifunction steering wheel, I am interested on this modification, do you have instructions or any link for this? I have a BMW Traffic Pro and want to figure out how to control volume and track-station from a streering wheel buttons.

  25. 25 On April 30th, 2009, jarda said:

    There are cars with a check control module and cars without it.
    Then there are OBCs with check control enabled, and OBCs with check control disabled.

    If you have a car with a check control module, you need to enable check control on the OBC, otherwise it won’t work and pressing CHECK will only light up all segments.

    If you have a car without a check control module, you need to disable check control on the OBC, otherwise it will always display CHECK CONTROL INACTIVE error.

    If you have a car with a check control module and check control enabled on the OBC, it will display CHECK CONTROL OK, or an appropriate error code if there is something wrong with your car.

    If you have a car without a check control module and check control disabled on the OBC, pressing the CHECK button only lights up all segments on the display.

  26. 26 On August 20th, 2011, Ron said:

    Hi, I was one of those guys that had his OBC display go belly up. I surmised that it was due to parking my 1999 328is in the clubhouse lot in Las Vegas. I got a reference as to the OBC’s cost by pricing it from the local BMW dealer at $850 plus software update costs. So. I bought a used one from eBay for $80. Once swapping out the unit I got all the same problems of “check control disabled-see the dealer” messages and tried all the fixes delineated in this blog. Since it was just the display, I did a lobotomy on the OBCs (an 18 button unit), initially using the eBay printed wiring board mounting the processor and associated chips. Upon mounting it the result was the same….and because I always do things a minimum of twice, I swapped out the eBay board and mounted my original. With failing eyes I individually soldered the connecting leads a second time. I removed the connector-like device which initially fooled me that it was, but it was just plastic strain reliefs. I found it was easier to solder each wire individually. Once together with my original printed wiring board mated to the eBay display module (including its associated driver electronics), it came up with all the original “check control okay” indications after entering the date and time. Test code #11: EINHEIT B3:FF and #15: DIAG: 01 05 255 F2 are my canned entries that was on my original printed wiring board. I probably could another 18 button OBC lobotomy in the dark, but wouldn’t want to.

  27. 27 On September 5th, 2011, Magoo said:

    Hi i have read through each and every post in 2 of your blogs entries. I am still lost as to if the check function will work on the 1996 318 i. I am blind and some of the tables added here are not possible for me to read. We went from a 7 button to an 11 button OBC, it is gibing the old inactive check owners manual etc.. The only funciton that seems to work is when it lights up all pretty.. I am tyring to help my oson do this as i use to work on cars when I had sight but it is hard to keep a 17 year old focused. lol… One simple wuestion i have to start off here is.. How do I tell if we have the check control module at all. the mention of the left speaker etc. above the foot is ok, but how do you get there to see. Also, I must correct my self, he can get to the country codes as well but there is no option for Canada.. Which is where i am. Tony do you ahve any more updates for this, did you get yours to work in the 318 IS/

    I thank all in advance and I am sorry if this has been answered but after reading so many posts my ears are crossed.. ( thats a blind joke cause i use a screenreader ) lol

  28. 28 On October 22nd, 2012, Martin said:

    So, yesterday I fiddled through every possible einheit 1 value, with einheit 2 set to FF. None of them worked. Today I fiddled through the einheit 2, setting it to 00, then I changed einheit 1 to 01. It worked! Two months of research and everything I needed was a little bit of luck 🙂

    so, here are two ways to do it (12h clock and 24h clock), worked for mine 1995 320i:

    Einheit2 set to 00
    Einheit1 set to 01 (12hour)

    Einheit2 set to 00
    Einheit1 set to 02 (24hour)

  29. 29 On April 9th, 2013, me said:

    how to deactivate “check inactive”….unlock obc at test 19….get to test 11 …put EINHIGHT 1 TO 7C,EINHIGHT 2 TO FF then press set\reset buton and should deactivate the check inactive ….all that is aplaing to all 18 buton obc….in my chase work’t fine…the mesege doesen’t apeear any more……