Not that it matters, but in Bentley, I see a Bl-R (blue red) wire going to
brake warning light module "K".

After the 4 pin connector at dash, there's another 4 pin connector "in
connection".

" Since the lights work when I jumper the two reds, giving power to
red-black from red-yellow,"

What red wires are you connecting?

On Fri, Oct 9, 2015 at 11:42 AM, Jim Felder <jim.felder@gmail.com> wrote:

> OK, thanks for that. As I have time to troubleshoot, I find I am getting
> red-yellow hot all the time as is normal. Blue-gray connects the two
> switches as a fail safe and runs off to the brake warning light just in
> case both fail, I suppose.
>
> That means that red-black is the problem, I think. Red black goes to a
> four pin connector that comes out of the dash, obviously going back to the
> lights. Since the lights work when I jumper the two reds, giving power to
> red-black from red-yellow, I suppose the problem is between the switches
> and the 4-pin connector. I will try to check that out now.
>
> Jim
>
> On Fri, Oct 9, 2015 at 1:26 PM Neil N <musomuso@gmail.com> wrote:
>
>> You have an '82 diesel? Looking at that in Bentley.....
>> S8 supplies constant (battery) + to brake switches via a red/yellow wire.
>> This wire enters one switch connector then splits off to the other.
>> You should see constant 12 volts at each yellow/red wire.
>> In a similar manner, a red/black wire goes from one switch connector to
>> the other,
>> becoming 1 red/black wire which carries + to brake lights when either
>> switch closes.
>> You should see 12 volts at either wire when brake pedal pushed down.
>>
>> Suggestions:
>> (likely NOT the cause) test brake lights with brake warning light
>> disconnected.
>> Test brake lights with one switch plugged in at a time.
>> Test brake lights while moving wires to switches.
>>
>> Ground is constant.
>> FWIW brake light ground is at "in connection box"
>> ..... whatever that means.  ;)
>>
>> Neil.
>>
>> On Fri, Oct 9, 2015 at 10:23 AM, Jim Felder <jim.felder@gmail.com> wrote:
>>
>>> Another thing, if anyone is so inclined to do so, I need to understand
>>> how
>>> the switches are supposed to work. It looks to me like there is always
>>> power to the switch, and the pressure interrupts the ground, which is the
>>> bottom of the U-shaped arrangement of terminals, the two opposing
>>> terminals
>>> being red and red yellow wires, so maybe it is the ground wire I need to
>>> chase down?
>>>
>>>
>>>
>>> On Fri, Oct 9, 2015 at 11:43 AM Jim Felder <jim.felder@gmail.com> wrote:
>>>
>>> > Bought two new switches this morning and installed them. No brake
>>> lights.
>>> > When the connectors are jumpered (the two opposing positions) both
>>> brake
>>> > lights come on. Getting power to them obviously. What else could be
>>> wrong?
>>> > Still out there with a voltmeter and a bentley, trying to make sense of
>>> > both. If the brake light switch connectors are getting power, and the
>>> > lights come on when the power is jumpered, and the old parts were new,
>>> and
>>> > the new parts are newer, then what else could there be that keeps these
>>> > lights from actuating? I just don't get it.
>>> >
>>> > Jim
>>> >
>>> > On Fri, Oct 9, 2015 at 10:36 AM John Rodgers <jrodgers113@gmail.com>
>>> > wrote:
>>> >
>>> >> My experience with the lights when not working has been to take each
>>> >> fixture apart and clean the heck out of the connections getting rid
>>> of any
>>> >> rust and corrosion. Made sure there was good metal to metal contact
>>> where
>>> >> needed. Cleaned all lenses and lubed the seals with a little silicon
>>> >> lubricant, then reassembled them.
>>> >>
>>> >> Never dealt with a switch failure. That's a whole 'nother horse!
>>> >>
>>> >> John
>>> >> On Oct 8, 2015 20:43, "Stuart MacMillan" <stuartmacm@gmail.com>
>>> wrote:
>>> >>
>>> >> > I’ve had way too many of these fail.  And, for some reason, they
>>> seem to
>>> >> > fail at the same time.  Supposedly, if only one fails the brake
>>> warning
>>> >> > light should go on when you apply the brakes, but that has never
>>> >> happened.
>>> >> > Aftermarket suppliers can’t seem to make switches that can take high
>>> >> > pressure for very long. If the dealer still sells them get them
>>> there,
>>> >> they
>>> >> > are just too important to take chances.
>>> >> >
>>> >> >
>>> >> >
>>> >> > Stuart
>>> >> >
>>> >> >
>>> >> >
>>> >> > From: Jim Felder [mailto:jim.felder@gmail.com]
>>> >> > Sent: Thursday, October 08, 2015 3:13 PM
>>> >> > To: Stuart MacMillan; vanagon@gerry.vanagon.com
>>> >> > Subject: Re: Help me diagnose and fix no brake lights
>>> >> >
>>> >> >
>>> >> >
>>> >> > I have the three-pin connectors, but shorting the facing two causes
>>> the
>>> >> > brake lights to work. This isn't among the last work done, it was
>>> done
>>> >> two
>>> >> > years ago when I did the brakes and suspension. That's not a very
>>> long
>>> >> life
>>> >> > for a brake switch, in my opinion. I wish I could remember when I
>>> got
>>> >> them
>>> >> > from so I wouldn't make the same mistake twice.
>>> >> >
>>> >> >
>>> >> >
>>> >> > Thanks, all. I'll let you know if the new new switches work, but I'm
>>> >> > pretty sure that's going to be it.
>>> >> >
>>> >> >
>>> >> >
>>> >> > Jim
>>> >> >
>>> >> >
>>> >> >
>>> >> > On Thu, Oct 8, 2015 at 3:54 PM Stuart MacMillan <
>>> stuartmacm@gmail.com>
>>> >> > wrote:
>>> >> >
>>> >> > First, short the two wires on each switch together and see if the
>>> lights
>>> >> > go on.  If not, it's likely wiring, if they do, it's the switches.
>>> >> Replace
>>> >> > both of them. It's not uncommon for these to fail.
>>> >> >
>>> >> > Stuart
>>> >> >
>>> >> > -----Original Message-----
>>> >> > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
>>> Behalf
>>> >> > Of Jim Felder
>>> >> > Sent: Thursday, October 08, 2015 12:27 PM
>>> >> > To: vanagon@GERRY.VANAGON.COM
>>> >> > Subject: Help me diagnose and fix no brake lights
>>> >> >
>>> >> > Daughter was driving behind me in the Westy today and called me to
>>> say
>>> >> > neither brake light was coming on. All other lights working. Brakes
>>> >> > excellent, newish MC and brake light switches.
>>> >> >
>>> >> > All fuses look good. Where should I start looking?
>>> >> >
>>> >> > Thanks in advance for your help. I need to head out of town
>>> overnight
>>> >> next
>>> >> > friday.
>>> >> >
>>> >> > Best,
>>> >> >
>>> >> > Jim
>>> >> >
>>> >>
>>> >
>>>
>>
>>
>>
>> --
>> Neil n
>>
>> Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
>>
>> 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
>>
>> 1981 Westfalia "Jaco" Images, technical
>> <http://tubaneil.googlepages.com/>
>>
>> Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>
>>
>

-- 
Neil n

Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>

1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>

1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>

Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>