1996 E30 clock, temp display
 

I'm sure there's some acronym for this square clock, date, and temp display next to my heater controls but I don't know what it is. I'll call it a SCDTD (square clock, date, temp display) and see if it catches on. Anyhow, the display would make one believe that at one point it displayed outside temperature. Mine reads -22 or something ridiculous like that all the time. I haven't been able to find any info in the Bentley manual. Wondering if I simply have a loose connection to an outside thermocouple but I wouldn't know where to look.

Chilly

First, you either have a 1996 E36 or an E30 (built through 1991?)

That display is called the On-Board Computer or OBC.

Yes, there is an external temp display in the OBC. The sensor is normally mounted through a hole in the left-hand brake cooling duct, but those ducts have a bad habit of falling off if the bumper is moved around by dragging on a curb, etc. Perhaps an event like that broke off your sensor?

As I recall, the sensor is a black wand, about 1/8" in diameter and 3/4" or so long, protruding from a yellow (?) block about 1" square, to which the wire harness connects.

Mine was still attached by the wire harness, so I attached it to some chassis structure behind the (now open) cooling duct opening with a zip-tie. Seems to work fine there.

Mis-typed. It's a 1986 E30.

Previous owner put the nose in a ditch once then installed a front spoiler over the banged up sheetmetal. Foglights were torn off so maybe this sensor is laying in a ditch, too. I'll fish around for the wire when I bring it out of hibernation.

Thanks,
Chilly