What are the common causes of no back up lights? Fuses and reverse safety switch seem good. Neither light works, no intermittent reverse lights while shifting between N-R-P. Thanks Dan

Hey Dan - Need to check the connectors at the tail lights to see if there is 12volts getting there.

Pull the conntector from the left light. Set the car up so that the backup lights should be on.

Of all the wires coming in, two are black. Check both, one comes from "up front" and the other goes to the right side light. If neither shows 12 volts, the problem is up front.

If one does show 12 volts, try this:

The connector has little tweezer-things that grip the circuit board contacts. The backup and fog (up to 1989) lights use the same method. Connection from up front grips the circuit board on a double-wide contact. The adjoining tweezer-thing grips the same double-wide contact and its wire carries voltage across the trunk to the right side.

The circuit board contact area under the tweezer-things coming from up front get oxidized and burnt and messed up.

The connector can be opened up. Determine which backup light contact comes from up front, and trade places with the one going to the right side. That way the tweezer-thing carrying voltage from up front will grip a good spot. You will get one backup light (as have I) and maybe a right side, too.

That connector is a little delicate, teeny-weeny little plastic ears holding the tweezer-things in place, etc. Take it slow and look carefully.



Problem up front is usually contacts in the P-N-P switch.

Good Luck,

Bob

:>)

It may be as simple as another bad bulb in the rear light area. That was what caused no reverse lights on my daughter's 1991 240.

Brian Mee

I had this happen in my '92. As it turned out, the wiring harness from the reverse switch came loose from its ties, fell on the tail shaft from the tranny, and was shredded.

Do try the tail light contacts first. And if that works, count your blessings.

Good luck.

--
Jim - '92 Red 245 193K, and sometimes an '85 245 275K+

Funny story: I got my 1990 240DL Wagon for $150 from a company that sells cars that have been donated to charity. The donor card had the words "No Reverse" scrawled on it. and they told me it would need a gearbox rebuild. I test drove the car a total of 10 feet before buying it: five feet forward, then, gingerly, five feet back into its space. It turned out that it had "No Reverse LIGHTS!"

Anyway, it's a pretty common issue, as I understand it, that the switch itself fails. Unfortunately, it may just be the hardest part in the car to get at. If the automatic is like the stick, you pretty much have to drop the gearbox. On the other hand, since it is pretty common, if the switch has been replaced previously, it has often been relocated. Are you the original owner, or do you have service records?

-EdM.
Franklin, MA
'90 240DL Wagon "Lola"
'72 1800ES "Galadriel"

I had similar problem recently on my 89 244 dl.Turned out to be dirty contacts where the wiring harness plugs on to the drivers side rear light assembly.The passenger side piggy backs off of it so neither reverse light worked.I simply cleaned up the contacts and stuck a little piece of foil on there for added conductivity, works like a champ.Could be your reverse switch too , or wiring, but I would check the simple stuff first. Good Luck!

Mine was a loose wire going into the connector that plugs into the drivers side tail light. Try putting the car in reverse (key to accessory, not on--you dont want to get run over) and start wiggling stuff. Not exactly technical, I know, but cheap and easy for starters.