Had manual tranny work done, and now no back up lights [Now Fixed]

[Rodger Tellefson]

O.K., I had the manual tranny in the shop for some shifting difficulties. Had a couple of forks & seals replaced (at no cost, btw, because they said that the forks should not have gone out in a yr. & a half). Checked the fuse first, and then the cable from the tranny to the brake light was made hot, and the back up lights do work. The question I have is where or how does the reverse light switch get activated inside the tranny? The workshop manual does not show this that I can find. Any help is greatly appreciated. I'll probably end up having to call the shop that did the work on Monday, but if I can get it fixed before then that would be great.

 

[Kevin Palmer]

It is normally an external switch. It is activated from inside the transmission by a bar moving either up against it or lateral to it and pushing in a ball detent kind of thing.

 

[Rodger Tellefson]

Kevin,



I am looking for a "picture" of how the outside switch is activated / contacted from the inside; whether it is a bar or a ball. We feel that the switch itself is good, although there is an outside possibility that it may have gone bad.



Thank You,

Rodger

 

[Kevin Palmer]

I can't help you with an internal picture, but i can tell you how to test the switch...



There should be a hot wire coming to it, when the switch is activated, the wire coming out will then get hot and activate the lights.



Test to see if voltage is GETTING to the switch, put it in reverse and see if the power passes through the light.



If not, remove the switch and activate by hand and see if you get the results you are after. If so, you have an internal issue.



Some of the switches operate a bit backwards, meaning, the ball-detent remains IN until a rod is moved out of the way and then the ball comes out and activates the switch. It is somewhat common for this ball to get a rust ring on it and remain STUCK inside of the switch. If this is the case, you will NOT get power through it no matter what as it simply is not going to allow the power through the switch..



Does this help???

 

[Rodger Tellefson]

Thank You, Kevin. Will post results in a day or two.

 

[Kevin Palmer]

Good luck...

 

[Steve McKellop]

Apologies for not getting this sooner Roger. They may have left the actuating pin out, see photo. It's removed/installed into the shift housing externally so it can be checked without disassembly.

 

[Rodger Tellefson]

Thank You so very much, Steve & Kevin. This is way I love this site.

 

[Rodger Tellefson]

The reverse lamp pin is there and the reverse lamp switch is good. So, I'll have to look deeper, or remove the tranny and take it back to the shop that did the work.

 

[Kevin Palmer]

If you get voltage through the switch, then the shop is going to say that it is not their issue. With one exception,,, If they somehow damaged the wire that runs FROM the tranny to the lights in the process of removing and reinstalling the tranny itself, (assuming you didn't remove it for them).

 

[Rodger Tellefson]

Kevin,



There is absolutely no issue with a damaged wire that runs from the tranny to the brake lights, as the brake lights do come on when the switch is made hot. That was the first thing that was checked after I ckecked the fuse.



I had a ASCE Certified mechanic who lives across the street remove the tranny for me because the shop, "Manual Transmission Warehouse", only works on transmissions that are removed from the vehicle.



We feel that there is something inside the tranny that is not pushing on the Reverse Lamp Pin that pushes on the Reverse Lamp Switch.

 

[Kevin Palmer]

I got ya..



If the switch is easy to remove, remove it and have someone put the tranny into reverse and see if the pin does in fact move.



In automatic Ford trannys there is a pin that slips into the switch. When you move the shift selector a rod in the tranny moves and hits this pin, then the pin itself is what actually activates the switch. I would think they do the same thing for manual trannys. If you can see the rod (or whatever) within the tranny move, then I bet all that is missing is the slip in pin.



Super easy to install as all it does is slip into the hole of the switch (which you will see once you unthread the switch itself).

 

[Steve McKellop]

Roger, do you know if you can remove the transmissions top cover/shift housing by removing the access cover in the floor? If so, that would beat dropping the transmission. Probably no such luck though.

 

[Rodger Tellefson]

I talked to the shop that did the work this morning, and he said that he switched out the top cover plate where the switch and pin are located. So, I will have to take it back next week, and he will put my original cover plate back in. Hopefully that will solve the problem.

 

[Kevin Palmer]

I am guessing it is simply missing the pin based on your issues and his comment..

 

[Rodger Tellefson]

From above . . .

The reverse lamp pin is there and the reverse lamp switch is good. So, I'll have to look deeper, or remove the tranny and take it back to the shop that did the work.

 

[Steve McKellop]

I don't know if that is bushings or spacers/multiple pins associated with the B/U switch in this view. Ask the shop about that and let us know, if you will. What activates the switch? Is it a normally closed switch and maybe a detent activates it?



Inquiring minds want to know.........:grin:

 

[Rodger Tellefson]

Thank You very much, Steve. I will be sure to let you know. I will be taking it back in middle of next week.

 

[Rodger Tellefson]

Put a [new] Reverse Lamp Switch in, and now it works fine. My guess is that even though the old swith was good, the contact the "Pin" pushed against was possibly worn.



Thanks guys for your help & support. :driving:

 

[Steve McKellop]

That's really odd, but quite possible. Glad it's cured!