2012 X3 Attempted Start - Just Windshield Wipers

[johnstewart]

I've got a 2012 X3. About a year ago I had an issue where I came out of work and it wouldn't start. But, bizarrely, when I hit the start button, the windshield wipers flapped. No other lights, no radio, nothing. We checked battery (voltage fine), and I was about to call for a tow, when we tried disconnecting the negative battery terminal altogether. After reconnecting it, the car fired right up, and everything was normal.

Fast forward to a couple of weeks ago. I come out of the Costco, and it's the same symptom. I tried the same "fix", but no change.... still, weirdly, just flaps the windshield wipers. The mechanic had said on a visit a few weeks before that the battery was questionable, so I bought a battery... but couldn't get it in because we'd closed the trunk and the battery was either completely dead, or it was otherwise totally hosed and I could not unlock the trunk. I got it towed.

The mechanic managed to get the battery replaced, and it seemed to be fine.

I drove it for a week, and this morning went to start it. Same deal. No response, but the windshield wipers flapped.

Voltage looks good (close to 13V) on the battery.

I'm going to contact the mechanic for ideas, but at this point, it seems like something is fundamentally screwed up with the "computer", whatever that means in this car.

I've searched and cannot find anyone having any sort of similar situation; has anyone heard of such a problem??

Here is a video I took of my attempt to start it this morning, after having removed the negative battery terminal, then reconnecting (the symptoms were no different than on the first attempt before I did this): https://www.youtube.com/watch?v=DYI53KDo2Dk

[johnstewart]

A couple of thoughts I had since I posted this:

- From the start for me with this car, it often complains about the tire pressure monitor system not responding. That unit was replaced just before I got the car. It happens maybe every 5th time I drive it (often, but not universal).

- Every once in a while, it gets "weird" about not wanting to open the doors with the unlock button (on dash, or keyfob). So sometimes I have to open the car with the physical key, or use the door handle to unlock the door if I'm inside.

- A handful of times in the last month or so, none of the buttons worked on the steering wheel (volume, cruise, etc). None of them. On the subsequent time I used the car, it worked fine (sometimes just a few minutes later)

- A few times lately it's been complaining about not detecting the key fob. I did replace the battery in it recently, because it did completely die at one point. But even with the brand new battery, I'll get in car with fob in pocket, it'll complain that it can't detect. But it's always started up.

So, electrical / computer gremlins, it seems.

Is there a component that runs ALL of these systems?

[johnstewart]

My exact symptoms: https://x3.xbimmers.com/forums/showthread.php?t=1618433