Diode ID

[TK]

Boy, that's a really simple ECM!


-----Original Message-----
From: Ludis Langens <ludis at cruzers.com>
To: gmecm at efi332.eng.ohio-state.edu <gmecm at efi332.eng.ohio-state.edu>
Date: Monday, June 07, 1999 2:12 PM
Subject: Re: Diode ID


>Matt S Bower wrote:
>>
>> Need help here.  I have a 6870 with a blown diode.  If any of you guys
>> can help me I would be greatful.  It's labeled CR1 on the board and it's
>> a small glass diode.
>
>CR1 is part of a circuit that clips negative voltage spikes on the ECM
>power input.  Check this schematic page (the 6870 and 7170 use the same
PCB):
>
>  http://www.cruzers.com/~ludis/1227170sheet7.gif
>
>You probably need something that can conduct the current of a rectifier
>and switch at the speed of a signal diode.  If you want to use a genuine
>GM diode, most (all?) C3 generation ECMs have this same circuit.  You
>could pull a replacement from something other than a 6870.
>
>--
>Ludis Langens                               ludis (at) cruzers (dot) com
>Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/
>
>