You may be on to something there. "Low DC resistance and higher impedance as frequency increases" describes properties of a coil or inductor.

Raymond

Sent from my iPhone

> On Sep 15, 2014, at 11:35 AM, Jon VonOhlsen <jondvo@GMAIL.COM> wrote:
> 
> Well, coil is either Spule or Induktivitat in German. Not sure about the
> 'B', but based on the high current flow & subsequent damage, looks like
> a ferrite, which would have low DC resistance but higher impedance with
> frequency.
> A schematic or an undamaged ECU would provide the answer.
> It does appear consistent with high reverse current damage. Have you
> ohm'd out both sides of the C208 cap to see if one side is ground? This
> would be the same as the mtg screw hole, most likely.
> Jon
> 
>> On 9/14/2014 4:09 AM, Roy Nicholl wrote:
>> If they were adhering to IEEE 200-1975 (in effect at the time), BT would be battery and there would be no ambiguous 'B's
>> 
>> 'B' can also be used for a 'blower' (or 'motor'), but that is also unlikely in this instance.   Is the schematic for the ECU available someplace?
>> 
>> Given that ECUs are endangered, does the list knowledge know if anyone has attempted to transfer the functionality into software - which could be run on a rather inexpensive embedded system?   Obviously such a solution would be costly as there would be insufficient demand to scale, but it would make it possible to add an OBD interface to the Vanagon :-O.   ... of course, it would probably be more effective to simply add a Subaru flat-four with its proven computer control system.
>> 
>> 
>>> On 14-Sep-2014, at 05:45, Raymond Markett wrote:
>>> 
>>> Wow! It looks like reversed polarity or a short caused a high current and burned the components. R usually stands for resistor, D for diode and C for capacitor. B usually stands for battery but that doesn't make sense in this case. I would guess that B202 is a inductor or coil. L usually stands for coil on U. S. schematics, but maybe VW uses B for the B field associated with a coil.
>>> 
>>> Sent from my iPhone
>>> 
>>>> On Sep 13, 2014, at 9:40 PM, Neil N <musomuso@GMAIL.COM> wrote:
>>>> 
>>>> Hi all.
>>>> 
>>>> As promised, the gory details. Images of my partially fried ECU:
>>>> 
>>>> https://picasaweb.google.com/musomuso/Motronic29ECUBurnedPartsEngineStillRan
>>>> 
>>>> Can anyone take a guess at what this part is, or was?   ;)
>>>> 
>>>> B202 shown here:  http://tinyurl.com/qxeceae
>>>> 
>>>> My close up shots are usually better. Sorry for poor quality images. I
>>>> generally don't use my good camera while in the shop.
>>>> 
>>>> Neil.
>>>> 
>>>> --
>>>> Neil n
>>>> 
>>>> Blog: tubaneil.blogspot.ca
>>>> 
>>>> '88 Westy http://tinyurl.com/c8rlw6p
>>>> 
>>>> '81 VanaJetta 2.0 "Jaco"  http://tubaneil.googlepages.com/
>>>> 
>>>> Vanagon VAG *Gas* inline-VR Engine Swap Group:
>>>> 
>>>> http://tinyurl.com/d7gd5ej