Cruise Control micro switch

Michael McKelvey posted:

@IaM-Ray thanks for continuing the conversation.

Instead of using the brake light thing on the master cylinder, could I tap into a wire going to the brake lights in the rear?

If I use the wireless switch, it would be nice to keep all of the wiring in the rear of the car.

 

Instructions from CruiseControl Store....

If you use the wires that simply goto a brake light ....

using a 5 port relay.. NO (normally open)

86 is fed 12 volt from brake light, i.e.: gets 12 volt when you press the brake....  feed from a tail light... 

85 & 30 get a GOOD ground,

87A goes to the White with Brown Stripe on the CPU from rostra, 

87 has no connection. 

This becomes, the press brake and turn off cruise part. 

•This forgoes using all the fuss of micro switches etc. 

@chines1   

Check out .....>>>>  Report of Cruise Control install   

@Joe Fortino 

@Marty Grzynkowicz

IaM-Ray posted:

Finally, from the tech at Rostra directly, since the circumference of the drive shaft is 12.5 inches I am presently adding two more magnets to double the pulses.  Why? when the system was originally designed most cars had 3 inch diameter drive shaft and thus about 6 inch around which worked well in the past but now with 12 inches the CPU needs to see more pulses.  easily done. 

Update, the circumference is actually 12&3/4inch which caused a bit of an issue as with two magnets the VSS, vehicle speed sensor, was getting confused since it was meant for a normal drive shaft diameter.  So I then tried 4 magnets and it worked albeit I could not set the speed well.  

You could set it but it would shoot up 5km and then down 10km then settle at the set speed.  Very large fluctuations in speed.  

Finally tried 3 magnets as suggested by Rostra, equally spaced at 4.25inch which is giving a good constant signal and when I set it,  it holds the speed set and can negotiate hills and climbs. 

It was nice to be able to drive one hour at 70mph and rest my foot.  

This will make long distance cruising much more relaxing.  

UPDATE: .... I was able to use the Rostra between 60- 70mph but I did not feel the unit did well at slower speeds due to my inability to get a good VSS on 12.75inch circumference.... Others may find it works well if they can get a VSS that works.

It started me thinking since I have a stock ECU that has the Cruise built in  ... I started doing more research and I will be going with this .... 

Well, I was thinking in about using magnets on the CV joint.  Do you think more magnets would help?

How many hours did you spend on the project so far?  I really would like to have cruise for Tour de Smo'.  On the other hand, I would really need it only once or twice a year for trips to Carlise, etc.

Well, it does work if your happy with 60mph to 75mph range... You would use 3 magnets on the closest axle joint near the tranny.  It just is not as flexible or elegant but you can cruise all day at 70mph.

If I did not have a subie ECU I would keep it, but the ECU can be made to work. 

A better VSS like DannyP is able to use, would make it more usable,  and I think the Rostra unit that DannyP will be using is what you would use as well as you need an electric servo to pull the throttle cable. 

I had that kit on a VW Rabbit years ago and it worked well but the axles were much smaller. 

How long does it take, well it depends on how long it takes for you to create two safety switches on the brake and cluch. 

Essentially attach a micro switch for the clutch arm on the tranny, then you need a micro switch on the brake or use the brake switch.  You could, if you find that difficult to do for the brake use the wires going to the brake light and run them to a relay. and use the relay to activate the  kill switch on the rostra cpu to put the system on pause... 

that way you brake or clutch in and the system pauses. 

it takes time but is not too difficult. 

I'm wondering if you could mess with the DIP switch settings for sensitivity, Ray. That can make a huge difference in performance.

I remember adjusting all that when I installed my first cruise control(Sears & Roebuck) in the 80s on a '77 Scirocco. It already had a plastic vacuum reservoir attached to the hood and I put a T in the line. Worked fantastic once the sensitivity was adjusted.

As I recall, it had 2 magnets on an inboard CV. Attached with nothing but a Ty-rap.

This unit did not have any dip switch features....

Working on the ecu stock cruise features as we speak

Carry on, gentlemen— tis is absolutely a worthwhile project. 

Shout out to M&R link ... they operate the cruisecontrolstore.com.  They were great to work with and are in Michigan.  They had agreed to work with me to modify and see if we could get the system working with my custom version of a car and they gladly participated in the R&D with return of goods possibility if the system did not pan out. 

FYI, with these types of projects running wire is probably the most time consuming thing if your wanting to have it look like Carey or Henry did it.  So you can save some tech time by doing all the wiring and switch installs, if your able, if your not, and your in Saginaw. 

They do in house installs locally @Michael McKelvey  should one decide to have them do it or want help. 

Yeah, it's about an hour and a half drive for you, Michael.

@IaM-Ray, @DannyP, thanks for mentioning the cruise control store.  I was aware of them and I talked to them about using a relay on the wire going to my brake light.

I am unsure about attempting this before Tour de Smo' although it sure would be nice for that.

I was thinking about putting magnets on the CV joint but after Ray's experience, I wonder if I might want to use another approach.

I was under the car yesterday and there is not a lot of room to work when installing a switch on the transmission clutch lever.

  You can get a micro switch that has a long arm so long as you can make a small bracket that will hold it depressed on the clutch arm    That should work   

Michael fox Was very helpful

Does it need a "Micro Switch" (A Honeywell, "Snap-Action" switch) or just a switch?

If all it needs is a switch without the snap/positive action of a Honeywell Micro then you could use a bake switch from an early GM product, which already has the arm that could ride against the clutch pedal arm.  If you're interested, an Echlin SL 128 or 132 (both NAPA part numbers) should work, just bend the arm to rub against the pedal arm.  I've been using one as a stop light switch now for years.

Michael, Ray has a drive by wire, different than what we'll be running. We will have an electric servomotor, and there are sensitivity adjustments in the main box via DIP switches. Magnets on a CV joint work fine.

Danny is right what happens is that you need a proper VSpeedSensor, and with a Drive by wire Rostra kit I am limited.... with a servomotor you have a full manual kit,  do it your self in the box and you may be able to adjust the sensitivity via DIP but I am not able on a DBW pedal kit.  

My switch is similar to this and it has a choice of normally open or normally closed and ground.  A flat bracket is what I used for attachment to the tranny, and it is adjusted, to be fully depressed so that when you move the clutch arm by depressing the clutch is cancels the cruise. 

Essentially, the ECU, is looking either to receive 12 volt at one port to cancel or to be grounded so both can be done and if there is an issue a relay can be activated by this microswitch.

@IaM-Ray, did you consider using the Rostra clutch switch and decide against it for some reason?

Yes I did, if you look at the switch it can also be used the only reason I did not was at the time I had not yet created a plan as to where I could attach it.  Either way you have to create a bracket to hold the switch depressed, up on the clutch arm, and when the clutch is depressed it has to change..usually breaking the circuit.

Update if you follow or reread the beginning of this thread I also investigated a way to add a micro switch to the pedal cluster.  In the end I found the easiest was the clutch arm and wiring the brake circuit like it was a brake light, that is to a relay, with it you can do what you want either send a positive or negative to activate or break the circuit. NC or NO. 

I have been reading what I could find about the topic on theSamba.

One message said if you have the tach connection on the coil you don't need the clutch switch.  The unit will very quickly sense the RPM increase and shut off.

Another said you could use the tach connection to sense spark pulses for a speed indication.  I don't know if this was for a Rostra installation.

Yuu can do a brake switch and bypass the clutch switch, M&R can telll you how ... you brake first to unhook the cruise anyway at least it is the most normal reaction... if you clutch in the engine will rev up so most of us do not clutch in we hit the brake. 

Magnets generate a pulse to a sensor... GPS can be used but sometimes it is inconsistent as a VSS.  A cable speedo can also be used via a piggy back unit. 

FYI, A VSS usually sends 4000 pulses per mile or at least that is what the Rostra unit is looking for so talking to M Fox you can get a more exact and detail approach to installing a unit in your car.

BTW @Michael McKelvey the CPU on the rostra has two ports for brake and two ports for clutch... one port can accept a GROUND out and another a 12 volt pulse for each type. 

You can get more info and a better understanding if you talk to Michael Fox over the phone. JUst saying.

Speaking of pulses per mile, I have been wondering what effect, if any, tire circumference has.

I thought maybe the cruise control doesn't care what my speed is or the per mile number of pulses.  It just holds my current speed, whatever it is. 

Tire size will affect the accuracy of the speedo reading (duh) but likely will not affect the ability of Cruise control to hold that incorrectly displayed speed.  Tire rack, and other source too, will give you all these numbers so you can figure out if a new tire may change the way your speedo works.  these days, it may even be possible to reset the claibration on the speedo if tire size changes to get things back to right.

The VSS Number of pulses has to do with the division the CPU makes to determine how fast your going and they often place dividers to reduce the number of pulses.  It happens sometimes that it cannot make a proper division.  Hence it gets confused and you can either a condition that it shuts down, or pulses... I had all the above on this trial.

These guys make a unit for Type 1 transmissions.  It might be a good alternative to the magnets on the CV joint:

http://www.vancafe.com/product-p/rmw-ch395ss.htm 

The second one here senses the CV bolts, no magnets needed:

http://fastforward.ca/vehiclespeedsensors/

Maybe this will help:

https://www.ntwonline.com/revolutions-per-mile-chart

Multiply number of magnets x revs per mile to get pulses per mile. Easy peasy.

My tires are 24.7" in diameter, so about 840 to 845 revs per mile. 4 magnets gives 3360, 6(CV joint bolts) gives 5040.

Thanks.  I still don't quite understand why the cruise control needs to know revs per mile.  It seems like it would just need to know if you have a constant speed, decreasing or increasing speed.

I guess the pulses need to be within a certain window for the ecu to properly count them, then maintain that count.

And by revs per mile, I'm talking revolutions of tire, not engine revs. And yes, some cruise controls can use a tach output for speed info. Probably not a good idea on an automatic, but fine for a stick.

Revolutions cause so many pulses within the specs of the cpu of the cruise control parameters as Danny said ... it just has to march up so that the cpu does throw a code and go limp

FYI, I just spoke to M&R and Michael tells me that they have a GPS with a persistent signal that produces the 4000pulse per mile and he can hook it up to a Rostra unit.  So there is another solution that is available.

As for me, I have been able to get info on the ECU and since I have full subie the VSS of the tranny is my solution.

Thanks for posting those VSS sites they are interesting to know that companies have addressed the issue in other ways for Vanagon's

Neet sites for sure as long as the VSS produces the signal range that you need for the Rostra unit it would work...  Michael Fox and M&R can advise if not Thomas is the senior engineer at Rostra who advised me on all the custom stuff and even made a custom CPU module for the drive by wire voltage range of my car which was different than other Subies.   So if you ask the right questions and know what output the VSS will give you with what you want to use then you can go forward. 

@Gordon Nichols, with your brake light switch, did you disconnect the switches on the master cylinder?

Michael  I just added one for safety sake

@IaM-Ray, what was it you added for safety sake?

Michael McKelvey posted:

@IaM-Ray, what was it you added for safety sake?

I just thought about it and while I did add a seperate brake relay to operate the cruise control shut off it is still dependant on the brake light working my bad

With the added relay I did not have to go near the brake switch on the master cylinder.   @Michael McKelvey

Michael, I don't know if Gordon left the switches in the master cylinder or merely plugged the holes(10mm x 1.0, but he is using a switch on the pedal to activate his brake lights, and I believe always has.

If anyone is interested in ordering from the Cruise Control Store, I discovered that if you order from them on eBay shipping is free but if you order on their website there is a shipping charge.

Mike wrote: "Gordon Nichols, with your brake light switch, did you disconnect the switches on the master cylinder?"

Yes, but just left them in place with no wires to them. If/when they leak (and you just know they'll leak, someday...) I'll just put plugs in