Strange and frustrating R53 problem

[nostar]

I have a 2005 Mini Cooper S, 65,000 miles, with a frustrating problem. Every so often, completely out of nowhere, the SES, EML, and tire pressure lights come on, and the throttle control dies and leaves me only able to go about 15-20mph untill I shut off and restart the engine. Then its fine for anywhere from minutes to days. So far it seems to only be at low speed city driving. Ive been putting in hours on the highway and it hasn't happened yet.

I got an ELM327 bluetooth scanner and the torque android app, and the last time it happened I checked the codes:

P0652 - Ref circuit B low voltage
P0700 - Transmission Control System Malfunction
P1768 - ???

Code P1768 is defined for other vehicles, such as Honda, etc but I cant find any definition for a mini cooper. I'm doing some city driving now, to see if it comes up again... Meanwhile, what if a controller sets an undefined code?

I just ordered the OBDLink SX usb scanner from scantool.net, to make sure the generic elm327/torque app isnt feeding me bogus info.

[AMcUK]

Checking the simple things - are you on the original battery?
First battery on my Merc went after 5 years and it caused some weirdness before it was replaced.

[-Nik-]

Bad plug wire possibly? Mine did that once , bad wire, was running on three cylinders.

Nik