Name that idiot light
 

On a 1983 300sd, does anyone know what the idiot light between the fasten seatbelt light and the outside temperature gauge is? It is a red light with no icon; it comes on periodically for approximately 1 second.
Thanks

Not sure, don't have one to check, but a glowing red light sounds like the warning that your charging system is not up to snuff and you are running on the battery when the light comes on. A little higher engine speed and you likely see the light go out. Typical sign of brushes wearing out on the alternator. Jim

... the 83 SD has no outside temp gauge... you must have a newer cluster in your car, and they put the bulbs in the wrong place.
I agree, a wavering light sounds like the battery indicator, it could also be the brake light though.

I’m pretty sure that the exterior temperature gauge is stock in an 83sd. The manual also calls the gauge out in the dash description.
Just replaced the alternator it is charging fine, the alternator/battery light is functional and is to the left of the temperature gauge as id the break and break pad wear indicator lights.

Nope, we have an '83 300SD, and it has no temp gauge. It was not stock till '84 or '85 I believe....

My friends 84 SD has the temperature gauge.

How about a photograph of the instrument cluster in question?

any chance your car has the airbag option?

[QUOTE=AdrianMiura;2028017]I’m pretty sure that the exterior temperature gauge is stock in an 83sd. The manual also calls the gauge out in the dash description. QUOTE]

Nope.

it's possible it's an option in that year... but my 83's to not have it. both have mbtex seats though, so they could be lower optioned cars.

No mbTex in this car.
Sorry my digital camera is non functional. However I’m thinking it may be the seatbelt light. I will need to remove the cluster to confirm this but the PO was involved in an accident and the front apron was replaced I have the suspicion that the cluster was also removed and either replaced or put back with the light in the wrong position.
I would confirm that with just removing the seat belt while the engine is running, but the light in suspect and the seatbelt light don’t come on consistently.