I just wanted to share with you how I conquered the dreaded "PPPP" code on my OBC in my 1989 525i.

My old OBC was working fine, but the digital display panel material had internally flaked off to the point where the numbers were not intelligible. I got quotes of $1,250 from my stealership and about $850 from Bavarian Autosports for new ones.

I instead ordered one used from the fine folks at Bavarian Auto Recycling for only $125 plus shipping. I had my indie import mechanic remove the old one while he was doing some other work to the car.

I checked this forum and others for advice on how to reprogram the new one. Some of this is not new information to board users, but it is what worked for me. I am sharing this because I realized after reading enough frustrated posts that this replacement procedure can be an ordeal.

Here is what I did:

1. With the car and power off, plug in the new OBC unit.

2. Turn car power on with key, but do not start car (radio works but ignition is not cranked.)

3. Push the "Code" button.

4. Push the S/R button.

5. Now without powering the car electrical system down, start the car.

6. Program your new unit which should be displaying 00.00 for the time setting.

I cannot attest to this being the textbook way to do this, but it is what worked for me. The new OBC did not reset/reprogram itself and lose the fateful "PPPP" code until I actually started the car. I tried it the other way - just hitting Code and the S/R - and it didn't work.

One other thing. My stealership service folks are actually pretty nice here in Nashville and the disspelled one urban myth I ran into on my OBC replacement journey. On the E34 at least, the OBC does not have the ability to "lock down" or "lock up" the car the way the OEM radio units do. My otherwise very knowledgable indie mechanic said he did not want to mess with installing and OBC because of the lock out danger. I called the stealership, and they said on the E34's that is a myth.

Again, don't take any of this advice as law. We all know how finicky these cars can be and how different they can be model year to model year with their little quirks. But this is how I got a new/old OBC to reprogram. I hope this helps someone.

Coincidentally, the new OBC concludes a round of fixes, mods and additions to my car. Recently added new Borbet Type H wheels from TireRack, a Sony Xplod head unit and CD player, re-tanned the leather, added a euro-style front plate and a new OEM shift knob (5-speed). I am considering the blackout look in the spring as my car is the bronzit/champagne color and I think it would look good. I am not very good at cosmetic changes to cars, so I am going to let a friend at a body shop look at painting the aluminum trim black rather than shell out for a shadowline kit. He says it shouldn't be a problem.

When I get enough posts here and I am allowed to post pictures I will do so.

[they] disspelled one urban myth I ran into on my OBC replacement journey. On the E34 at least, the OBC does not have the ability to "lock down" or "lock up" the car the way the OEM radio units do...
Er, uh...this statement is totally confusing because...the OBC CODE feature isn't a myth..you actually CAN immobilize the car using the CODE feature. (instructions are in the owners manual) And second...the BMW anti-theft radio has never been able to "lock down" or "lock up" the car?

I think you have confused and jumbled two anti-theft features of two different components. :)

The OBC does have an immobilizing feature (which is explained in the owners manual if you have one)...when you press the CODE button on the OBC...you can enter ANY number from 0000-9999, then you press the S/R button to set it...then remove the key from the ignition. Upon the next start, the car will not start UNLESS, you re-enter the SAME number between 0000-9999 that you had previously entered. If you fail to do so, after the 3rd starting attempt, the car alarm will sound and the emergency flashers will go off. THIS IS NOT A MYTH.

The radio's anti-theft CODE is a static 6 digit number (never changes)...and if there is an electrical interruption...the radio's CODE must be entered for the radio to work...not knowing the radio's CODE will NOT affect the car's ability to start...it only affects the operation of the radio...which in this case...won't operate until the CODE is entered.

I hope this clears up any misconception you may have about the radio's CODE, and the OBC's CODE.
:D

I'm not confused, and, yes, I have the owners manual. I have also read it. I am completely aware of the OBC's code ability if programmed correctly.

I have encountered among fellow owners and mechanics in my research on this matter an almost supersitious fear of removing or changing OBCs because of this feature. The point is that the OBC must be programmed to set the anti-theft feature off on the car. An E34 OBC does not, in fact, have a pre-programmed code like the radio units do. That was the secondary point of my post. Sorry if it was confusing.

Clearly, if one care's enough to replace an OBC then one is going to own the car and know whether or not they pre-programmed their old OBC. The OBC does not retain any programming in an E34 once removed from the car nor does it retain any data.Therefore, even if an OBC were programmed to set off the alarm feature, once it was removed for surplus it would lose that programming.

My overall point was that removing or installing an OBC does not carry with it the same set of complications an OEM stereo unit carries with it having a pre-programmed code. Many folks seem to think that an OBC has this pre-programmed feature in an E34. Based on my research, personal experience and discussions with my dealership they do not.

The extent of my troubles while removing the OBC repeatedly (possibly driving the car without it, but I'm not sure) was that I had to reset the date and time, and it set the language back to English. PPPP flashed briefly when reinstalling it, but it works just fine now.

My overall point was that removing or installing an OBC does not carry with it the same set of complications an OEM stereo unit carries with it having a pre-programmed code. Many folks seem to think that an OBC has this pre-programmed feature in an E34. Based on my research, personal experience and discussions with my dealership they do not.

...now we're on the same page...thanks...that is perfectly clear and I concur with everything you said! :thumbup:

So in essence, does the procedure that Tenn525 wrote correct in removing the PPPP error code in an OBC??