Hello from (rainy) Wales!
I normally get all my questions answered here just by searching, but this time I need to ask the community for help.
Drove my '91 Trans Am (lb9,A4) into the my garage a few days ago to do some bodywork, went to start her up after finishing .. and no cranking, checked all the usual stuff, batt voltage, starter connections etc..jumped the purple wire to starter, engine cranks over with no start. came on here to research vats which I suspected, so I've been through the whole thing of going to the electronics store and soldering in a resistor of the same value as my vats key...still no cranking off the key.
So I'm fairly sure its the vats module itself (I still have some checks to do, vats connector, live from ign, vats earth etc) so I'm asking this in readiness, if it is the vats module Whats the quickest fix?? Its stuck in my garage and I need to get it out under its own steam asap.
Long term I'm happy to invest in chip burning equipment and delete vats that way, but right away I dont have time, bear in mind I'm in the UK and anything I order has to come over the Atlantic.
Any ideas would be appreciated.
I have a friend who's good with electronics, should I ask him to rig me up a box that puts out a 30 hertz (or 50htz) signal?

 

First things first , have you checked the VATS fuse ?

If no , and if you don't know where it is , it's not in the regular fusebox , it's in a little sub panel called the convenience center located in the dashboard right above your right knee , you gotta take the lower plastic panels off to get to it .

A picture of what your looking for ....

 

Hi OrangeBird, I should have mentioned I'v got a workshop manual (GM) for a 1990 (only year out!) and it says in there to check the vats fuse and ecu fuse and the gauges fuse which I'v done and their all good, however, they were all on the main fuse block, is there a second vats fuse in the convenience centre? or just different on y year to your pic?

 

In fact, I'll go check it right now, most of the dash panels are off ready.

 

Only two fuses on my convenience centre, thanks anyway OrangeBird, I don't want to leave any stone unturned before I have to pay for things.
Will be going over everything once more tomorrow.

 

Update, after spending hours tearing down the dash to locate the VATS module I started conducting tests as per workshop manual, and the first test showed up the problem which was no live from ignition feed. So i traced that wire back to the fusebox to discover some nasty repairs where a PO had spliced something in and then removed it..crimp connectors, insulating tape twisted wires etc.
As soon as I tidied that up and re-connected everything turned the key and she fired up on all eight cylinders as if nothing had ever happened.

Lesson learned here is....GM shop manual worth its weight in gold.

 

I know on the 91/92 the VATS is powered by the ecm fuse' circuit.