What is this switch?

[Dug Nichols]

Working on re-sealing the '71 Sahara acquired last Fall and I've come across a switch that I'm not sure about.

- the reverse light switch has no wires connected to it

- there are two cut wires hanging off of the wire run that is going to this switch in question

 

I was thinking that it might be a jerry-rigged reverse light switch... in this pic the car is in reverse and the switch is not activated. Any ideas?

 

Also, it's not apparent to me how to get the shift selector rod into a state that I can replace the seal. Is it comprised of two pieces that are joined where this switch is??

 

Lastly, as I'll be replacing the reverse light switch and seal (this definitely is the main culprit for the nasty leak and gunk everywhere) I'm wondering if I need to connect the switch to the cut wires, leaving this unknown switch in place, or use the wires that are on the unknown switch. I suppose getting a 12v supply and testing would the way to go (he answers his own question).

[coloincaalpine RIP 2021]

Never saw one of those switches.   Does the car perhaps have an aftermarket cruise control?

[Son of Marty]

I'm pretty sure that's ether part of the smog system of a neutral safety switch it was a 1 year only deal most have been scraped years ago.

[TobyB]

Emissions, methinks, along with a clutch switch.

 

If your emissions relays are not there any more, it's not doing anything.

 

t

[Conserv]

2 hours ago, Son of Marty said:

I'm pretty sure that's ether part of the smog system of a neutral safety switch it was a 1 year only deal most have been scraped years ago.

 

+1

 

Few of these switches remain in place. Even fewer remain functional. But the wires leading to the switch are generally still present.

 

My ‘73 (VIN 2762757, October 19, 1972) still has the wiring. And the February 1972 transmission I installed in the ‘73 — the original transmission had been replaced — still has the switch (first photo below). On this ‘73, the short crossmember that supports the rear transmission mount has two small clips to retain the wiring for this switch as the wiring runs across the transmission tunnel from harness on the left to the switch on the right (second photo below).

 

And the same crossmember from a ‘72 tii (VIN 2762204, July 10, 1972) I bought and parted in 1974 has the same two clips, leading me to believe ‘72 and ‘73 models included the feature (third photo below). Although this subject arises regularly, we have not clearly defined the population of cars which included it.

 

Regards,

 

Steve

 

Edited April 14, 2019 by Conserv

[Mike Self]

Regarding the switch--Steve's post above triggered a memory about that switch, and I found the reference in the BMWCCA's (no space then) 1976 Tech Tips book.  That switch was part of the seat belt warning system, and was most likely installed starting whenever the inertia reel seat belts were installed during the 1972 model year, along with the seat belt warning light.  The switch would trigger the warning light if the car was put in gear with the seat belts unfastened either driver's or passenger's side.  There was a sensor in the seat that would detect a weight in the seat (whether person or grocery sack, the sensor didn't care!).  

 

The tech tips writeup was about a hard shifting transmission, caused by this switch being misaligned with the shift rod and rubbing against the rod when it wasn't supposed to.  The cure:  remove the switch and tape the wires up out of the way.  

 

I believe this switch was dropped with the 74 and later cars (can anyone confirm this?) with the introduction of the infamous seat belt interlock, which prevented you from even starting the car unless seat belts were fastened.  That one didn't last very long!

 

That switch was missing on my '73 when I bought it in 1978, probably because the previous owner's wife wore out the clutch at 44k miles.  When the tranny was pulled, the shop must have removed both switch and wires, because my seat belt light never functioned from the day I bought the car.   But the clips in Steve's picture are still there, thus solving a little mystery of my own....what were those clips for?

 

mike

Edited April 14, 2019 by mike

[Dug Nichols]

Interesting! This car is a ‘71 and it has the clips on the transmission crossmember.

 

What’s a tip to get the selector shaft able to accept a new seal?

 

 

Edited April 14, 2019 by otto

[jgerock]

There have been several posts on this topic...

[jgerock]

1 hour ago, otto said:

Interesting! This car is a ‘71 and it has the clips on the transmission crossmember.

 

What’s a tip to get the selector shaft able to accept a new seal?

 

 

The shifter transfer rod disconnects from the tranny at the pinned coupling. 

[dang]

The coupler that you have circled has a spring steel cover on it.  Remove that and you'll see how it comes apart.

[Dug Nichols]

Awesome, thanks for all the great info everyone. I did indeed search extensively on the FAQ and across google, but wasn't able to find the answer dang provided. I should remember how this works, having done a 5 spd swap previously myself, but alas my brain had purged that bit of info...