What the heck is is it?

[joeinbcs]

Getting to know the '68 DeVille convertible I just got, I came across a device with a lever mounted to the driver side of the firewall, near the data tag.  It has a hard brake line going to the master cylinder, and a green wire spliced into the cluster just to the side of the brake booster.  I've checked with all my car buddies and nobody seems to have a clue.  Anybody here know?  Thanks!  Joe

[Cadman-iac]

  Joe,

 At first glance it looks like an old mechanical electric trailer brake controller, but that's not where one would normally be mounted. Typically it would be either on the steering column or under the dash on either side of the column so that the driver would have easy access to it when needed.
 And it would have more than just one wire going to it.
 When you press the brake pedal, does the lever move at all?
 It will be interesting to hear what it's supposed to be.

Rick

[dn010]

It's a Kelsey-Hayes electric brake controller. You can tell by the shape of the sticker that is gone. Definitely a strange installation location but perhaps the installer chose that spot so the brake line wouldn't have to come through the firewall and they figured they'd just leave it set to automatic.

[billyoung]

Also there should be evidence on the cars frame of where a trailer hitch was mounted and also maybe two holes down low on the rear bumper center face bar unless it also has been replaced.

[dn010]

Just found an example of what you have:
https://www.ebay.com/p/1536844370?iid=205032918888

[joeinbcs]

Thanks, guys.  Mystery solved...partially.  There's no evidence of a trailer mount at the rear of the car.  Is there any other reason this thing might have been installed?

[Cadman-iac]

Thanks, guys.  Mystery solved...partially.  There's no evidence of a trailer mount at the rear of the car.  Is there any other reason this thing might have been installed?

If not used for its intended purpose, the only thing that comes to mind is maybe they used it as something to control the brake lights. Is the turn signal switch operable? The switch in a tilt/telescopic column is now as rare as hens teeth, so possibly a work-around for this? It would require two wires though for that to work.

Rick

[bctexas]

Can you show what electrical harness it is connected to, and tell us what color wire it is spliced into?  Brake light switch is an interesting thought, but it sure seems like an expensive way to solve that problem vs the typical screw-in switch.  Interesting indeed!

[Big Fins]

I was going to say a line lock to the front brakes for staging at the tree!   

[dn010]

I was going to suggest that perhaps an owner down the line didn't want the hitch and went back to stock, but that would make no sense to remove a hitch but keep the brake controller. It definitely sounds like it was installed to do something it was probably not meant to do, as a workaround for some other problem.

[Cadman-iac]

I was going to say a line lock to the front brakes for staging at the tree!   

 I thought about this, but the problem is that the unit doesn't lock in place, as soon as you release the lever it returns to the "off" position.

   Rick

[Big Fins]

I was just being funny.

Actually seeing what harness it's hooked into will give you a better idea as previously noted. But, no clue why anyone would install a manually operated valve under the hood where it couldn't be controlled by the driver.

[joeinbcs]

So, it's a "one family" car.  The car was owned by the father of the seller.  He had a collection of about 400 cars of which this was part.  Did most of its miles in the first few years of ownership, then a lot of time in a museum until the old man's death, and the son's liquidation of most of the cars.
Here's a pic of the green wire connecting to the bundle of wires at the firewall.
Thanks to everyone for the interest, Joe

[bctexas]

Hi Joe!  It appears from the picture that the green wire from the brake controller is connected to the fat red wire in that bundle.  Is that correct?

edit - I don't have a '67 wiring diagram, but I do have a '68 Eldorado diagram in dad's old '68 shop manual.  That red wire is most likely the main 12v power feed from the hot post on the starter to the ignition switch - at least that is what it is on the '68.

[Cadman-iac]

Hi Joe!  It appears from the picture that the green wire from the brake controller is connected to the fat red wire in that bundle.  Is that correct?

edit - I don't have a '67 wiring diagram, but I do have a '68 Eldorado diagram in dad's old '68 shop manual.  That red wire is most likely the main 12v power feed from the hot post on the starter to the ignition switch - at least that is what it is on the '68.

 Yeah, if this was intended to be used as it was meant to be, there should be at least two, maybe three more wires going to the unit.
 One would be the 12V power source, which I would think is what we're seeing here, but also one from the actual stop light switch to turn the trailer lights on, and one going to the trailer for the electric brakes.

 I'm wondering if someone had just cut out the other wires for reasons unknown.

 Rick