Can I read the error code using ALDL?

[Eduardo Gimeno]

Hello everyone!
I've been reading everything about ALDL here, and I see that you guys want
to get all the internal parameters from the ECU through ALDL connector.
All I want is to know if I have then possibility of getting the error code
in case one is generated.
My car is Opel Ascona 2.0i, from GM, using Motronic. Other related readings
show the possibility of getting the error code shorting a couple of wires in
the ALDL connector, or pushing the accelerator for five times, and other 
things like that. The last one doesn't work in my car, and I'd like to know 
if the first one might.
I've been looking for the ALDL, and all I found is a two wires connector 
near the engine, and a 5 or 6 wires one under the dash (over the pedals).
Is the last one the one I should use (if I'm able to read the code by this)?
I know the method is shorting some pair of wires, and look at the flashes of
the light at the dash, count them, and look up in table (I already have them),
but, does any one how to get the light flash???
Thanks for reading and bearing my bad english and explanation.
Eduardo
<eduardo at ctv.es>