1969 Bay Brake Wiring Problem.

[garyb606]

The master cyl sending units both have a wire unattached. Three wires under the dash unattached and have no brake lights. The three wires showing under the dash are black and red stripe, black with red dots and green with a plastic connector. Image has reflections appearing to be more wires. Please help!!!

[telford dorr]

From Technical (an excellent reference):

First question: do you still have the 9-pin relay unit ("J" on the schematic)? Or has it been removed? If removed, find the green wire that should go to terminal 54 and the black/purple wire that should go to terminal 54S on the 9-pin relay, and connect them together. This is the brake light signal from the brake switches to the turn signal switch.

Second question: do you have three brake light switches (J1, J1 and J4), as shown in the schematic? I'm only seeing two in the pic. Looks like both J1 switches are there, wired in parallel, as they should be. J4, the brake check lamp driver switch, seems to be missing. I'll bet the two loose wires at the brake switches were the ones that were supposed to go to the third switch. If the third switch is missing (wrong master cylinder), tape up the two wires. Just understand that the brake check lamp on the dash is inop...

Third question: do the turn signals work? If so, what does the device that makes the clicking noise when turning look like?
_________________
'71 panel, now with FI
'Experience' is the ability to recognize a mistake when you're making it again - Franklin P. Jones
In theory, theory works in practice; in practice, it doesn't - William T. Harbaugh
When you're dead, you don't know you're dead. The pain is only felt by others.
Same thing happens when you're stupid. - Philippe Geluck
More VW electrical at http://telforddorr.com/ (available 9am to 9pm PST)

[garyb606]

Thanks Telford,
Only have two sending units on master cycl. It may have been changed but appears old and rusty as if the sending units may be faulty.

The turn signals do not work however, the front right side did work until today. Don't know why it quit bulb is good and fuses good.

I will try to get a picture of the turn signal flasher unit. The problem is that I do not feel proficient enough to drop the fuse box to see the flasher. I am afraid that wires may come off the fuse panel and not be able figure out where they go back and the fear that a connector will break and cause more concerns.

Thanks and please be patient with my inability to troubleshoot wiring.

[telford dorr]

Not a problem. We'll proceed at whatever pace you like.

What we're initially trying to determine here is whether you have a stock 9-pin flasher relay (68 - 69), or did somebody try to upgrade to a later early Bay wiring (70 - 71). The 9-pin flasher relay is NOT on the fuse block; the later flasher relay is. If it's an upgrade, we can't make any assumptions about the wiring, as it will all be modified, and we'll have to piece through it, bit by bit. Note: there's no reason a conversion should be any less reliable than stock, if done properly.

Here's the 1970 version for comparison:

As you can see, virtually all of the control components are different: flasher, 4-way flasher switch, brake switches, except for the turn signal switch, which is the same (this didn't change until 72).
_________________
'71 panel, now with FI
'Experience' is the ability to recognize a mistake when you're making it again - Franklin P. Jones
In theory, theory works in practice; in practice, it doesn't - William T. Harbaugh
When you're dead, you don't know you're dead. The pain is only felt by others.
Same thing happens when you're stupid. - Philippe Geluck
More VW electrical at http://telforddorr.com/ (available 9am to 9pm PST)

[Tcash]

Don't be afraid to remove the fuse box.
Be sure to disconnect the battery - negative cable first.

Do you see one of these under the dash.

Good Luck
Tcash

[telford dorr]

Thanks, tcash - good stuff.

The upper two images are the 9-pin flasher we're looking for.

All of the lower images are possible flasher relays that may have been installed in its place.
_________________
'71 panel, now with FI
'Experience' is the ability to recognize a mistake when you're making it again - Franklin P. Jones
In theory, theory works in practice; in practice, it doesn't - William T. Harbaugh
When you're dead, you don't know you're dead. The pain is only felt by others.
Same thing happens when you're stupid. - Philippe Geluck
More VW electrical at http://telforddorr.com/ (available 9am to 9pm PST)

[Yarkle]

read this and see if it helps...mid 69 is a hybrid between the 68-69 and 70-71 diagrams

http://www.thesamba.com/vw/forum/viewtopic.php?t=587348&postdays=0&postorder=asc&start=0

and check this diagram -kind of buried in the thread

http://www.thesamba.com/vw/archives/info/wiring/bus_69fuses.jpg

the gist is: "When VW abandoned the `67/`68-style hazard flasher system in mid`69 Bentley never published a proper diagram to reflect the change. Same goes for the change from three 2-prong brakelight switches to two 3-prongs. Follow the `70 diagram for these circuits on a late `69, but power them from the appropriate fuses rather than the ones shown for the 12-fuse panel. "

ALSO: all of your fuses should be 8 amp-white
_________________
Tilda the Mustard Tigress 1973 Squareback (o'''^'''o)

https://www.thesamba.com/vw/forum/viewtopic.php?t=771024&highlight=

[Tcash]

Please see
Bay window bus brake wiring

Thank you
Tcash