Re: Reading Fault codes on '89 100

["Scott M." <scottmo@teleport.com>]

Jeff,

The procedure that Phil outlined from the 3B 20V engine is
the same for the 89 200T/Q but the documentation I have
indicates that the 89 100 uses only two diagnostic
connectors (one black and one brown, same location, under
the driverside dash). 

You may not have the "check engine light" bulb installed,
there was an unpublished campaign to remove these bulbs as
they had too many false alarms with the engine light coming
on....Mine was removed on my 89 200TQ, had a dead knock
sensor and did not even know......

The documentation for the 100 shows a black and brown
connector as Phil described, but no blue connector. Connect
the LED positive terminal (LED's are polarity sensitive) to
the top black terminal, and the negative LED terminal to
the bottom terminal in the brown connector. Use a jumper
wire between the bottom black connector terminal and the
same bottom terminal in the brown connector to short for 4
seconds then remove jumper, to initiate the fault codes
(ignition key on, with or without the engine running), but
turn the ignition on before you short across the two
terminals, otherwise you may enter the "output" mode that
tests the various solenoids and systems controlled by the
ECU.

HTH
Cheers
Scott M.
89 200TQ
CHIPDIPPINDUDE

Jeff said:
> I still have an intermittent low idle problem with my
1989 100 automatic.  I
> believe I have a wiring fault but have been unsuccessful
at pulling the
> engine codes.
> 
> I don't believe I have a check enging light on my car. 
It has been
> suggested to me that I might have a light but it isn't
inserted into the
> dash display.  Another suggestion is to pull the codes
from the connector in
> the passenger footwell.  After searching the archive I
found one of Phil's
> posts describing this procedure for the 3B engine with
motronic ignition
> which I've copied below.  Will this same procedure work
on my car or will I
> fry something.
> 
>