thunderbirl

Sunday, a week ago, spent the day at a festival and were in and out of the rear hatch. At the end of the day, I got a pile of warnings and the clock needed to be reset.

Next day, I packed my suitcase in the back and drove to the airport for a two day trip - and came back to a totally dead car. AAA had to come jump start it. Once home, every subsystem reported (using Autoenginuity) low voltage.

Friday morning, the car was nearly dead after taking some stuff out of the rear on thursday night.

The 7 month old battery got checked out at Autozone as "100%". The "UB" service menu gives before starting as 12.2+ when all is well. This rises to 13.8+ when the car is running. (My E350 gives about +0.2 higher on both those readings.)

I had a similar incident last winter, but wrote it off as the battery, since it tested low after 4.5 years... now I'm wondering if there was something else.

I never have the issue at work - but I also never use the rear gate to or from work.

I think I'm seeing that as long as I didn't use the rear gate, I didn't have a problem. The rear latch makes a pretty serious moan everytime it would lock and I'm thinking that it's just too dang tight. Maybe it wasn't actually latching - though it never gave me a warning about the gate being ajar.

So- I took the catch/strike plate apart and adjusted it outward by about 1 mm (1 division of the markings of the plate) - and it latches promptly with little/no noise. There's still pressure on a piece of paper placed in the gasket. There is no water seepage from a pressure washer.

The other things I've done were to pull the battery and have it tested and I unplugged and reseated every connector in both SAMs. There was no hint of moisture or water anyware.

What have I missed?

Thanks for any ideas.

sheepdog8

Checked the smaller auxiliary battery?

thunderbirl

I don't have direct evidence that the aux battery is 100%. However, when I removed the service battery to have it checked, I didn't loose any settings anywhere - other than the clock. The radio reverted to 87.5 MHz, but just needed to be set to a preset - which were all preserved. All "optional settings" of lighting and dash were fine.

It's hard for me to believe that a problem with the auxiliary battery would present as a completely dead vehicle and yet be fixable with a jump.

As an aside, I'm not at all clear as to what this little (and I mean little!) battery actually does! I see suggestions like it powers the setting of "park" so that you can move the car if the main battery takes a dive. I've looked and not found anything that seems very authoritative. This aspect is probably worth a separate thread.

I'm quite sure that the service battery is OK. If someone can tell me that the auxiliary battery can kill the main battery in a random fashion and present the symptoms I've seen, I'll try replacing the little guy!

ntshuma75

Good friends,

I need your help I have a Merc C200 Kompressor, auto transmission and it is giving me a flashing ESP notice on my dashboard. This has been going on for the past two days. At times when Im driving it I here a sudden strange noise that causes the car to jerk. Pliz help Im clueless as to what maybe wrong