Cruise Control Operation

[bugfil]

I have a VW cruise control unit(VPC-Volkswagen Products Corporation), Part # ZVW201709, Type 2, and manual transmission kit ZVW201728 that I bought NOS on the Samba many years ago and installed it many years ago too.
It works well as long as you don't have to go up a hill that's steeper than 3 degrees.
I have a question about the operation of the unit. When I apply the brakes while using the cruise control it slows down as long as I am depressing the brake but when I let up on the brake pedal it starts to accelerate again meaning the cruise control is still engaged. This is a little disconcerting when you are used to a modern cruise control that cuts off when the brake pedal is applied. There is a cut off switch on the clutch pedal but not on the brake pedal.
Is this the way this cruise control is designed to operate or did I install it incorrectly? Does any one else have one of these installed on their bus that could comment on whether theirs work this way too?
The installation manual mentions an operators manual but I did not get that with the unit so I'm not exactly sure how it is supposed to operate. It is a manual transmission in a 78' Champagne edition Westy.
These units seem to be pretty rare and I have found very little information online about their operation.

[busdaddy]

I see a clutch switch, does it disengage when you push the clutch?
There must be a brake switch, I've never seen a cruise control of any brand that didn't cut off when you touch the brake, what's the wiring diagram in the install instructions show?
_________________
Rust NEVER sleeps and stock never goes out of style.

Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!

Слава Україні!

[Bobs67vwagen]

Yeah something is not right on this. When the brake is applied the cruise should be deactivated by a switch on the pedal. Maybe another Audi/VW car of the same period that has cruise control might be a place to start looking for wiring and components for troubleshooting advice and information.

[rsbadura]

[bugfil]

Yes Busdaddy, the clutch disengagement switch does work correctly. There was
no wiring diagram provided in the install instructions. Here are the other two pages provided in the install instructions. I have not gone back in to look at
the wiring etc. yet. I believe the system has always been this way since I installed it so it may be connected incorrectly but I don't see anything in the instructions that describe or show a switch at the brake pedal.
Thank you for the manuals "rsbadura", having a wiring diagram to look at is very helpful. On page one of the manual I see a picture of the chrome stalk and switch end that looks like the one in my set up so they may be the same or close. I see in the trouble shooting section that when the bus continues to accelerate after releasing the brake pedal it is either a faulty engagement switch or faulty regulator. Sounds like I may need to learn more about how this system works to determine what's wrong.
Thanks "Bobs67vwagen" good idea about looking at other vVW/Audi models from the same years, that may help me see if something is missing from my cruise control.
I'll let you know what I see when I take a look at the cc system tonight.

[bugfil]

Hi, so I pulled the front pan to look at the cruise control parts. I didn't see anything I can recognize as being wrong, of course that's with my very limited knowledge of cruise controls and how they work. How often does a guy who has worked on aircooled VWs for 40+ years need that knowledge?
Here are some more photos, definitely no switch for the brake pedal.

Here you can see the switch on the clutch pedal.

I'm thinking now that maybe the unit is electrically tied to the brake light as the brake does seem to shut the cruise control off temporarily. I'm not fighting the motor still trying to drive the vehicle forward when the brake is on so I believe something is cutting power to the cruise unit.

Does anyone out there know how to test for proper function of the different parts of the cruise control. I'm particularly thinking of the regulator since the information rsbadura provided says in the trouble shooting section that when a cruise unit acts like mine does it's either the switch or the regulator that is not working properly. Any ideas are greatly appreciated.

[busdaddy]

I wonder if the resume switch is stuck on, although it quits and doesn't resume when you clutch, correct?

No idea on the "regulator", is that the thing with the speedo cable on it?. It kinda looks like the GM system from that era, I figured out how that system worked years ago so I'll try and recall where I found that info.
_________________
Rust NEVER sleeps and stock never goes out of style.

Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!

Слава Україні!

[67rustavenger]

I would move that clutch switch to the brake lever.
The way it's currently installed, when you depress the clutch pedal while driving, it seems to me that the engine would rev up before the pedal is completely down and disengaging the CC.

I never liked those bead chain CC's.
We installed one in a 32 Ford Coupe some 40 year ago and had an incident when we hit the accelerator and the chain slack got wrapped around the brake lever. We almost hit a Walnut tree before we could switch off the engine.

To the person that commented on later model CC in their driver.
I have a 2003 EV Weekender and a 2020 Tundra TRD. I have to be careful driving the EV as the Tundra has radar detection and will slow mu truck as I approach a vehicle ahead of me when the distance closes rapidly.
My EV doesn't have the radar feature so, I have to remember to touch the brake lever in the EV when driving it and the approach distance closes in traffic.
_________________
I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!

There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo!
2003 Astrovan? GFYS again, Xevin!
Don't let your bad ideas remain, ideas!

[rsbadura]

[mikedjames]

Read the first set of instructions you posted. There is a wire from the brake light switch mentioned in the bottom right paragraph.

There is no need for an extra switch on the brake pedal, there is already a switch.
_________________
Ancient vehicles and vessels

1974 VW T2 : Devon Eurovette camper with 1641 DP T1 engine, Progressive carb, full flow oil cooler, EDIS crank timed ignition.
Engine 1: 40k miles (rocker shaft clip fell off), Engine 2: 30k miles (rebuild, dropped valve). Engine 3: a JK Preservation Parts "new" engine, aluminium case: 26k miles: new top end.
Gearbox rebuild 2021 by Bears.

1979 Westerly GK24 24 foot racer/cruiser yacht Forethought of Gosport.
1973 wooden Pacer sailing dinghy

[bugfil]

So, I’m still trying to sort the problem out. Lots of ideas but nothing I’ve checked is wired wrong or connected incorrectly.
Mikedjames, I have read that part of the install section numerous times and double checked the wiring in the brake circuit, everything gets power like it should all the way to the CC regulator and power is cut when the brakes are applied. The problem is the CC comes back on when the brake pedal is released which it should not do. This is specified in the instructions too. Any ideas why depressing the brake pedal doesn’t cut the power for more than the time the pedal is depressed?
I’m wondering about the resume feature on this CC, which I haven’t checked into yet. There is so little information on these CC units that I can find even though these Dana Speedostats were use on many different vehicles.

[busdaddy]

The factory one in my Chev truck stays off after you touch the brake (separate switch on pedal), it'll resume when you poke the resume button, I can't remember if it remembers the speed when the ignition has been off.

Yours sounds like the resume switch is stuck.
_________________
Rust NEVER sleeps and stock never goes out of style.

Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!

Слава Україні!

[blacka1vw]

Could there be an input switched between the brake switch signal and the clutch pedal signals? Maybe resuming after clutching could be ok.
_________________
64 SC truck.
71 Beetle -Skyy
71 Super -Sweet pea
73 Bus
79 Bus -Tic Tak
86 Cabriolet