O3 3 liter started then died after about 3 seconds. Then would crank but not fire over. Got out locked the car and unlocked it thinking it may be a security issue. Would not start. Next morning tried again- no start. Had it towed to the dealer and got a call that, just to see, they tried to start it and it started. Now what. Extended warranty covers labor and parts but not diagnosis. This intermitent aspect worries me because I could be stranded at any time any where. Any ideas? Don

 

The first suspicion with an electrical problem in the S-Type is always a dying battery. How old is yours, and do you regularly check its cells and add water as needed? That's a requirement if you intend for your battery to last for a long while. These cars suck up power like an anteater sucks up ants....

 

Or water/damp in the trunk (or elsewhere).

 

Did the dealership, as part of their diagnostic procedure, check to see if there are any fault codes present?

NBCat

 

I had a similar issue.I could get some of the electronics to work but not all. I couldn't jump it using the from "Jump Posts" in the engine bay. I finally got it jump connecting the battery booster to the battery in the trunk. Under warranty, drove to dealer, battery replaced and everything worked fine after that. If you can jump it from the battery in the trunk and if things seem to work (powered by alternator) then I would replace the battery. Not sure what happens if you completely disconnect the battery. Some cars need resetting after completely disconnecting the battery and you can prevent that by plugging in a device while battery disconnected. However, if the battery was tested at a parts store battery was already out so likely not an issue at this point. Good luck.