Hey, take a look here....
Seems that our friends with BMWs suffer the same problem - again the
BD438 transistor seems to be the point of failure.
I wonder if there is a beefier power transistor that you could replace
the BD438 with that would not be so prone to burning up?

http://www.unofficialbmw.com/repair_faqs/idle.html

Todd
'88 Westy

David Beierl wrote:

> At 06:03 AM 1/22/2003, Frank Condelli wrote:
>
>> problem was.  The transistor the electronics store gave me as a cross
>> referenced replacement was a NTE 332.  All I know the motor ran with the
>> burned transistor but had idle stabilisation problems and the motor
>> would not
>> run at all after changing the transistor.  I am now using a used
>> newer model
>
>
> Ok, the Motorola BD438 PNP silicon (4-watt) power transistor pinout is
> ECB,
> looking at the printed side, left-to-right, leads pointing down.  C and B
> appear to be slightly closer together.
> http://onsemi.com.cn/pub/Collateral/DataSheet/bd438rev7.pdf
>
> And the NTE332 is BCE...so it definitely needs an attitude readjustment.
> http://www.nteinc.com/specs/300to399/pdf/nte331.pdf
>
> You may or may not have wrecked the replacement -- or possibly other
> things
> on the board.
>
>
> Incidentally (or not) NTE lists the NTE185 as the proper cross for a
> BD438
> -- and its pinout is pinout is ECB, like the Motorola.  It's also in a
> case
> that's a much closer match, no heat sink sticking out of the top of the
> case.  I didn't look at the electrical specs of any of them.
> <http://nte01.nteinc.com/nte/NTExRefSemiProd.nsf/5f94e45f99cb39c785256a8400531fe4?CreateDocument>
>
> <http://www.nteinc.com/specs/100to199/pdf/nte184.pdf
>
>
> david
>
>
> --
> David Beierl - Providence RI USA --
> http://pws.prserv.net/synergy/Vanagon/
> '84 Westy "Dutiful Passage"
> '85 GL "Poor Relation"
>