Informational bit...
I bought this 1988 244DL for $450 that was running on 3 cylinders. After diagnosing and replacement of the #4 exhaust valve spring with the help of you excellent people at Brickboard, I now have a wonderful little Swedish Kitten that purrs away. I then moved on to the little niggling items.

Backup lights! Since this will be my 16year old daughter's driver, I wanted everything working and in good order. The BL's would not light. Went through all the postings, checked the Neutral/Reverse switch, inspected the transmission BU switch, nothing obvious.

Now, the tail light housings are 23 years old, and the Brake lights had been dodgy, and the connector was always to blame, so with multi-meter in hand, to the tail I went.

What I found will shock no one.

The underside of the housing connection "bar" is where the connector's "jaw" clips make contact. Over the 23 years, the IC ribbon has been "mushed" down to the point where contact is lost or intermittent, and a shim is needed.

I had read some entries about shims, but wanted to try something non-conductive first. So, cut yourself some plastic from a light-weight plastic container, like what lunch meat comes in. Slip that between the "jaw" connector and the housing connection "bar" on the TOP SIDE, so as to bring the underside clips into stronger contact with the IC ribbon. This solved my problem (fingers crossed).

Hope this helps, and start here first rather than looking at the Neutral/Reverse switch or the transmission switch...Occam's Razor prevails! The simplest, most obvious causation is the one to inspect first!

Ah, old age gets to us all, and what was tight and delightful needs some work now and again.

Regards,
Bill