09 Jetta Sportwagen TDI

This cold morning (-3), I started my Jetta TDI without issue, scraped the windshield of ice as it was running, turned it off, went inside to get the kids, buckled them into the carseats. When I went to start the car again (10 minutes after I turned it off), the ignition was dead (no glowlight indicator, no turning over, no power to the instrument panel), but the interior lights were on, the fan was on, etc. Tried a few more times, same thing. Went to neighbor who has TDI to ask if there is some magic button I could press, came back (less than 3 minutes later), and it started up fine with full power to instruments. Any thoughts?

Sounds like it might be a loose or corroded battery connection.

I’ll guess that turning off this diesel so soon after starting in -3F weather somehow confused the glow plug timing. Next time, just leave it running.

Concur w/@texases … a similar thing happened to my Corolla last winter. On the coldest day of the year. In my case when I turned the key to “start” all the instrument panel lights went out. Happened all of a sudden-like, at a gas station. When I hadn’t had any kind of electrical problem at all for months.

It turned out one of the battery connections had come loose. Not completely, but loose enough I could twist it by hand. I think the explanation involves some kind of unequal thermal expansion between differing materials, and somehow the warming up of the engine compartment that occurred when you first turned the engine on caused it, and the cooling down that occurred when you waited a while fixed it.

One point I always forget to suggest if the battery connections seem okay is to check the battery posts (if you have posts) to see that they’re secure in the battery. I got fooled once by a battery whose post was broken free inside the battery. It isn’t common, but it does happen.