98 Plymouth, immobilizing device shrting?

Hi- A friend of mine asked me to see if I could find some information for his problem. He has a 98 Plymouth Grand Voyager SE. At times his van does not start and it appears that some kind of security system is activated. When he inserts the key and turns to ACC none of the dash lights/gauges activate like normal. Similary, when the key is turned to START, the engine does not turn over. It is like the battery is dead EXCEPT that the dome light works, power door locks/windows, etc. He knows the car wont start as soon as he puts the key in and turns to acc and the dash lights dont come one. Now, when he bangs the top of the dash it will usually fix the problem. I was thinking there was a loose ground (or +12) for the dash cluster and that is causing all the problems. However, I was reading other posts on the forum and it looks like the van might have a starter disable.. if this was shorting out and disabling the car, would the dash lights still come on????? I'm sure either way, he is going to have to tear the dash apart and search for the short, I am just trying to narrow his search. If it is the starter disable (vs a short in the dash wiring), then he could easily by-pass it to solve the problem. thanks for any help- Brad

A starter disable wouldn't prevent the dash from lighting up. Pull apart the dash and see what you got in there.