You can throw money at a problem or you can take a little time to analyse it.
Problem: The starter suddenly stops for no apparent reason when you are cranking the engine over.
Solution 1:
Carefully examine everything electrical that is part of the starting circuit. The ignition switch, the small connector on the wiring harness that connects to the starter solenoid from the ignition switch, the switch at the transmission that senses when the transmission is in Park or Neutral, etc., etc.
Finding a wiring diagram might be a bit difficult, but you might find something that helps at Ack's FAQ (
http://www.acksfaq.com). Go there and do a search for
tracker factory service manual. The results of the search will take you to the master index page. Towards the bottom, you will find
Volume 2 Section 8A-30 Starter and Charging. Over the years, not much has changed mechanically with the Suzuki Tracker/Vitara - especially those with 1.6 L engines. You will find that the resulting circuit diagram will come very close to describing what you have on your Vitara!
Eventually, with patience, you will find the problem and be able to fix it.
Solution 2: Take it to the dealer and let them figure it out for you.
Solution 3: Keep throwing money at the problem.
BTW, Solution 3 is the worse possible solution. It always costs the most - unless you get
extremely lucky.
I would try Solution 1. It costs less, you get the satisfaction of knowing that you are in complete control of the situation and there is that great feeling that YOU figured it all out!