wmf62

just a heads-up for those who are using the Audiovox cruise control and might want to add LED brake lights.

the cruise may not work anymore. i discovered that mine would no longer 'set' after installing the LED light assemblies. apparently not only the flasher may not work, but the cruise may not work.... the LED lights don't draw enough current to create whatever reference voltage/current draw that the Audiovox unit is looking for.

Plasticman made me a 'black box' with a relay and resistor that goes inline with the purple wire that provided the correct reference that the Audiovox needs to see.



and now i have cruise control again... thanks John...

Bill

Plasticman

Bill,

You are entirely welcome.

Just a "little" additional info:

The cruise control purple wire supplies a voltage to the brake light side of the brake switch. The cruise control "expects" to see this voltage essentially shorted to ground through the low resistance of the standard filament type brake light bulbs (we found it needed a maximum of 4 ohms to allow function of the cruise control). Any higher a resistance and the cruise could not be "set".

With the LED brake / tail lights Bill added recently, we measured over 5 VDC on the brake light side of the brake switch (when the brake pedal was not depressed). When we added a 3-4 ohm load resistor (connected to ground), the cruise control would function.

We were adverse to adding a permanently connected resistor or light bulb. A resistor or light bulb would be fairly high wattage and would need to be placed somewhere "safe" and yet let it dissipate it's heat - note that a 3 ohm resistor at 13 volts requires about a 60 watt resistor, and probably higher due to de-rating it depending on where it is located. A light bulb works better, since it changes (increases) it's resistance when lighted, and yet has a low initial resistance when cold (not powered). However, again safely locating it is a "problem", and note that this load resistor or bulb should be located somewhere around the brake switch, since the left and right brake lights get split into 2 separate sets at the turn signal switch, and we really only wanted to add one load. Bill did not want a "heater" (or a light bulb) added to his AC cooled cockpit!

So I designed a simple circuit to add the required load resistance for the cruise control, and yet remove that load resistor from the circuit when the brakes are applied (to eliminate the need for the high wattage resistor or light bulb).

Circuit is a 12 volt coil / 30 amp contact relay with "normally closed" (NC) contacts, and a 2.7 ohm 5 watt resistor. Only 2 external connections are necessary (one to ground and the other to the cruise control purple wire where it connects to the brake light side of the brake switch. It loads the cruise control purple wire and brake lights through the contacts of the relay to the resistor which then goes to ground. When the brake pedal is depressed, the brake switch supplies 12 volts to the brake lights and to the relay, which then opens the "normally closed" relay contacts, and opens the circuit to the resistor and ground (preventing the resistor from seeing high current).

I will post a schematic later.

Note that Bill's photo above shows 2 purple wires (and the black wire that is connected to ground). The 2 purple wires are connected (in the circuit) to the same location, and just provided a means to connect his cruise control (purple wire) to one wire, and the other went to the brake switch.

Plasticman

AZDoug

A/C, cruise control, EFI,a nd whatever else i can't remember. If you get the desire to add power windows and adjustable seats, maybe you should buy a new Impala and paint it Corvette color instead.

Doug

firstgear

or he is going to have to give Plasticman visiting rights to the car.....

wmf62

Doug
hmmm, let's see if i can figure what you left out....

ahhhh yes...:

4-wheel disc brakes
front air dam (your fault... )
power R&P steering
battery in the trunk
MY6 OD trans
LED tailights
front daytime running lights
side engine mounts
dual master cylinder
Hushmat insulation
push/pull cable operated windshield wipers
power antenna
14" steering wheel
Hurst shifter

power windows seem like too much trouble; and rolling the window down would let the a/c out... i do kinda/sorta like the cut-down C4 power seats that i THINK Charles Bernhardt made...

maybe i can get some Impala emblems to replace the corvette ones; which version would you suggest? SS, LT, ????

Bill

Plasticman

Here is a schematic:



Plasticman

Jackfit

Hi, I am having a problem with my Vox CCs. I installed one 5 years ago...worked great..stopped working....looks like diaphragm on servo let go.

Got a new unit...hooked up everything...all tested wires ...good, but when on road...will not set.

Trouble shoot all wires...they are getting right signal...

tried different settings on unit...no good...

Any suggestions.... regular lights no lEDs

Jack

wmf62

Had the same problem, made up a relay box that is different from John's box we originally used.

There is a cruise control that a motorcyle accessories company is having made that is an exact reproduction of the ccs-100. Do a google search and you will come across their site.

On the site are directions for building the correct relay for use with LEDs.
Bill

wmf62

Murph's kits...
Bill

Jackfit

( I don't have LED;s not the problem , just the opposite , power when you should not have any.


Hi, I have it working, but it turns off when I put the lights on, purple wire getting current when it shouldn't. Have to check my connections. My brake light circuit is getting current when the brake is not depressed, just lights on... it is not full 12v but enough to set off the sensor on the unit as if I stepped on the brake. Did not have that problem before new unit. My light sockets are original and have a bit of bubba (me ) to keep them working. I wonder if the two way (brake, tail light) bulb ends have corrosion and are bleeding current across the socket when I put the lights on.

Jack

Jackfit

Here are photos of my installation of the CCV 100 . It worked great for 5 years and 65,000 mile. Diaphragm in unit finally gave out. You can find the unit at Murphy's Motorcycle web page for about $175 , less on ebay if you can find it.

You hook up color coded wires to the brake light circuit . One wire to the coil, one wire to a hot wire that is on/off with key. Coded wires to the dash lights , to light the control unit .

Set the dip switches on the unit . Use the 8,000 rpm switch, (not what the instructions say) 1-7 numbered switches. For a corvette they should be 1 & 2 on (8,000) - 3 Off - 4 on - 5 & 6 Off - 7 On

Cruise Control makes driving a C-2 or C-1 fun again. You can stretch your legs and move them on longer rides.

Jack

wmf62

I suggest you make the Murth's kit box and try it, it should eliminate any stray signals
Bill

59BlueSilver

I've been reading this with much interest as I just bought a CCS-100 on EBay a couple of months ago and will try to install it next month. I also have LED taillights. I'm also not too good with schematics so I'm sure I'll have questions when the time comes.

Jackfit

It is very simple to hook up once you understand the principle of current from your brake light system controls the on / off signal. Follow the dip switch as I posted. Get back to me once you start. With LEDs your lights do not draw enough power to signal the unit to turn off when stepping on brake. The resistor put in line / or a bulb will then draw more current.



Jack

Jackfit

Hi, I had my unit working for 5 years. Servo unit ( diaphragm shot) stopped working. Replaced with new unit / wires harness. Unit works until I put on lights. Purple wire now gets 4-5 volts even though brake is not depressed. It get 12 when brake pressed, 0 when released. Only gets current when parking or lights go on.

Where is leakage coming from? To give current to brake line when not depressed. My brake lights do not come on with lights...

Jack

wmf62

Jack
I can state the obvious, you getting backfeed from somewhere.

John's original design relay box made the system work when we first installed it on the first ccs100' but there were still occasional cases where the cruise wouldn't work. We were going to try a larger resistor but then the first unit failed just like yours (gonna take it apart someday and see what the failure actually was...)

The new unit didn't work at all with the old relay box and I trouble-shot the circuit til I thought I would go nuts.

Finally, after more Google research I decided to build a relay box like the murph's box, and 'viola', it has worked perfectly every time.... As you know, the system works by shifting grounds, and that's what the murph box does.

There is a diagram of the circuitry on their website and it is very easy and inexpensive to build. John's box is not the answer.

Try it....
Bill

ohiovet

A similar situation can occur with Dakota Digital cruise control when using LED tail lights.
The fix is similar to WMF62's solution.
The other thing that happens with the DD CC is that the tail lights STAY ON all the time. Some sort of feedback situation. The car has to be in a very dark place as the lights are very very dim.
Bruce B

Jackfit

Hi , that feed back is what is turning off the control, when I put lights off, control resumes at last speed setting. I will test some more to try to find the point of cross feed.

Jack