by Cliff Knight - email@example.com
|After doing some research into aftermarket
cruise controls, not liking the "add-on" look of any of the stalk
mounted controls that came with most, and then being inspired by a posting
on Miata.net I set out to find an Audiovox
CCS-100 kit. I found one at Autozone in Daytona Beach for $99.95.
I understand that it may be available for less ($89.95 I was told) online,
(Summit Racing shows it in their
online catalog but doesn't list a price).
The photos below show the servo cable connection to the throttle body, the vacuum connection to the intake manifold, the servo/control module mounted on the driver's side shock tower, and the dash mount control panel mounted just to the left of the steering wheel.
|The kit consists of the servo control
(which incorporates the control module electronics), the dash mount control
panel (gray plastic like the inside of a Bonneville, backlit via two green
LEDs that connect to the dash lights), all necessary wiring including a
length of split loom (a nice touch!), a length of vacuum hose; and a wide
variety of mounting brackets, throttle cable adapters, screws, bolts, wire
ties, a grommet for the firewall, and vacuum tees and reducer couplings,
and more! In short just about everything you'll need. You may
need some other electrical connectors if like me you are adverse to Scotchlock
taps and connectors.
The servo/control module is 3-1/4" in diameter, its main body is a bit over 4" long with a 2" or so "snout" for the control cable. The cable's outer sheath extends 44" from the servo body, the exposed inner cable with the supplied ball chain and adapters cann add a foot or so to the overall cable length. The wiring harness for the servo plug has a nice snaplock single row plug-in connector (like an older PC power connector). This conencts to a header in the servo's wiring box, the wiring box cover has a dual foam seal that keeps the nasties out.
Click here to link to the CCS-100 manual from Audiovox' website (an Adobe Acrobat .pdf file)
Installation of the servo, and connection of the throttle cable and vacuum line, was quite easy and straightforward. The first photo above shows the cable connection at the throttle body, I used the parallel throttle cable clamp adapter and the longer of the two throttle wire loops that come with the kit. I tapped the vacuum line in at the rear of the intake manifold (the second photo), placing a tee (also included in the kit) into the hose connecting vacuum to the fuel pressure regulator. Inside the servo's wiring box there's a 7-position DIP switch that needs to be configured--in theory using the settings provided in the installation manual and reference guide (a 50 or so page tabular listing by make an model).
Switches 1 and 2 control the PPM (Pulses Per Mile) setting, allegedly for the speedometer signal (more about this later), the reference guide says to set this for 4,000 PPM--I did. Switch 3, Speed Signal, tells the control module whether you are using both the Tach and VSS (Vehicle Speed Sensor) signals, or just the Tach--I set it for both, this was wrong (more later). Switches 4 & 5 set the unit's sensitivity (LOW for light vehicles with high HP, MEDIUM for most vehicles, or HIGH for low power/heavy vehicles), I initially set this to MEDIUM. Switch 6 tells the control what kind of control switch you're using, normally open or closed (the included dash mount switch unit is normally open). The last switch is the Tach Select Source, ECM (Engine Control Module) or COIL (duh!). For the Miata set this to ECM.
The third photo shows the servo (the electronic control module is incorporated into the servo), mounted on the driver's side using the bolt that holds my custom diagnostic connector bracket. I also used one of the M6 hex head sheet metal screws from the kit to further anchor the servo. With this arrangement (servo on the driver's side by the shock tower), the servo cable and included vacuum hose fit nearly perfectly--in fact the under hood installation has a very "factory" look.
The CCS-100 requires a number of connections to your car's electrical system, Unfortunately, the wiring instructions are quite generic and therefore can be misleading and confusing. From the servo unit, there's a short (15" or so) black wire from the servo unit with a 6 mm ring connector that needs to be connected to a chassis ground (I used the servo mounting bolt), and a blue wire that connects to the -Ign terminal in the diagnostic connector (I tinned the twisted wire, and just "plugged" it in to the diagnostic connector). There are 6 wires (actually 5 wires and one coaxial cable) that have to go through the firewall. I punched through the rubber seal for the main harness just below the fender mounted relay panel and dragged 'em through with a wire coat hanger.
The coaxial cable terminates with a black and a gray lead that are intended to connect to the VSS--for the NA Miata they say to connect this to the RSW (Reed SWitch) terminal on the rear of the speedometer; don't bother (more about this later). Two more wires connect to the stoplight switch, a red wire to the "hot" side of the switch (the white/green wire on my '90), and a purple wire to the "output" of the switch (the green wire). There's also a power pigtail (orange) with an inline fuse, and a red wire coming out from the fuse holder, that needs to be connected to a power source that is hot when the key is on (I used the cigar lighter power).
The other wires (the red wire from the power pigtail, and yellow, brown, and green wires from the servo/control module), have Molex type pin connectors crimped to them and connect the to control switch using a 4-pin Molex connector (like a hard drive power connector). I mounted the control panel in the rightmost of the three auxiliary switch locations (photo four) to the left on the steering column (I think the OEM rear window defroster switch goes there). The switch blanks are two-piece affairs, I removed the center plug and just stuck the control panel to the surround using the preinstalled double sided tape. The panel's cover snaps on (and therefore off), so I popped it and have painted it satin black--I lost the silk screened Cruise Control, and Accel and Coast labeling, but I think I'll be OK...
So, I got it all in and rechecked my connections (including the RSW connection, the grey wire, to the speedometer), and took to the open road. Accelerating to 45 MPH or so I turned on the unit and pressed the Set button--releasing the accelerator in anticipation of some controlled cruising. I instead got nothing, nada, zip--no cruise control, back to the shop.
I once again checked my wiring, and the control module's DIP switch setup. Everything seemed OK, but on a hunch I changed the Tach signal source to COIL, my reasoning being that the 1.6L Miata doesn't really have a modern type ECM signal (the signal at the diagnostic connector is the same signal that fires the ignitor)--back to the road. Nothing, no cruise control...back to the barn.
I got out my wiring diagrams and looked at the RSW. It's just a reed switch activated by the viscous magnetic coupling in the speedometer, one terminal connected to ground, the other just dead-ended at the RSW terminal. I.e. it is NOT an active signal, it could "pull-down" a signal to ground, but it does not generate any pulses per mile. Remembering the Speed Signal setting (DIP switch 3), I set that to Tach Only and disconnected the gray wire to the RSW terminal--back to open road...
I got up to 45 or so, turned it on and pressed Set, and immediately felt the servo take over, YAY!!! Let's try 60 MPH, says I...
Nothing, it won't lock in. Playing with it I found that it wouldn't Set at any speed over 52 or so, and also 52 was as fast as I could accelerate to using the Accel function--back to the garage...
Trying to control my frustration (and having to get this thing working before the wife got home and found out I blew $100) I got to thinking about this PPM, pulses per mile thing. The manual says this setting works in conjunction with the VSS (RSW in the Miata) signal, which I had now disconnected. But since the Miata uses a wasted spark ignition system I thought I might as well try the 8,000 PPM setting--I mean heck, the worst thing that can happen is that I let the smoke out of my $100 cruise control unit (and she can only kill me once)--back out to open road.
OK, 45 MPH locked, let's go for 60... YAY!!! I'm cooking, so let's find a secluded place where the FHP doesn't go...
Cool, 90 MPH and locked!
That's it--don't bother with the VSS (gray wire), so there's no need to yank the instrument cluster. Set DIP switches 1 & 2 for 8,000 PPM, switch 3 for Tach Only, and switch 7 for ECM (I switched that back when it didn't work on COIL). I used it today on a 100 mile round trip to Jacksonville and found that it worked well, but seemed a bit sluggish on what passes for hills here in NE Florida. I stopped and changed the sensitivity (DIP switches 4 & 5) to LOW (light vehicles with high HP) and that fixed it, it now holds the set speed within +/- 1-1/2 MPH or so.
So, the bottom line is that this is a nice, inexpensive, very compact cruise control kit that works well. The installation instructions are a bit too generic, and use inconsistent nomenclature, and the recommended connections and settings for the NA Miata (at least the 1.6L models) are just plain wrong, but once set up correctly I like it!
This is my experience installing an Audiovox CCS-100 in a 1999 Miata. First, I laid the servo by the brake master-cylinder located on the drivers/ side of the hood, and let the cable wrap around the engine over to the throttle cable assembly. I removed the factory throttle cable from its' place in the gold-colored roundish assembly, which gave me room to attach one of the audiovox-supplied cable connectors into a separate slot similar to the one that holds the factory throttle cable, but above it about half an inch. I attatched about a dozen of the supplied links of ball chain, and then hooked the chain onto the audiovox servo cable. The servo cable was then attached with the supplied adjustment nuts to the same black metal that secures the factory throttle cable, just an inch or two directly below. I assume this is the way a factory servo cable is installed, but have no way to verify. Regardless, it's very slick looking and effective. Be careful not to tighten the servos' adjusting nuts too tightly, as this is a hollow and weak piece of threaded metal prone to breaking. I mounted the servo unit to the body by taking one of the supplied brackets, L-shaped and about 6" long. There is an empty bolt-hole about 2" behind the diagnostic center which is the little gray box mounted to the driver-side fender by the shock strut. I took a bolt about 2" or so long and ran it through the straight end of the L-shaped bracket. Underneath, I added three oversizd nutsd to act as spacers to elevate the height of the servo, and screwed the bolt in tightly. I angled the L-shaped end of the bracket toward the passenger-side, and using the seventh and ninth holes in the bracket, fastened the servo using a couple of bolts and nuts also supplied by audiovox. Using this method, the servo is straight in line with the engine and gives a very professional look. Would have been nice if the cable was a couple of inches longer, but it is long enough to work respectably, and looks good. Also, to provide stability, I used a tie strap to fasten the rear of the servo unit to one of the hoses coming from the brake unit.
The intake has two vacuum outlets that have black rubber caps. I used the rear one, and had plenty of vacuum hose to reach. I used a couple of black tie straps to secure the throttle and vacuum lines.
Wiring is a piece of cake, once it's understood that audiovox has things way over-complicated. I first did the only tricky connection, which is the blue wire from the servo. I cut off the section of this that has the noise-suppression on it, and ran it inside the diagnotic center, which again is the little gray box by the shock strut, only about a foot away from where the servo is now mounted. To get it inside, remove the diagnostic box from its' bracket, I forget exactly how, and then disassemble the box which is held together by some tricky little plastic components. Play with them for awhile…you'll figure it out. Once inside, you need to remove the black electrical tape from the bottom of the unit, which will allow you to slip the blue wire inside along all the many other wires. Locate a wire that is mostly green with an orangish-yellowish stripe. There should be a brown wire on one side of it, and a black wire on the other side of it. Strip off about a quarter inch of insulation from your blue wire, twist it, and use a pick or tiny screw-driver to force it in and make connection with the green and orange-striped wire. This doesn't seem too professional, but is effective. Put the box back together, and leave the blue wire alone for now.
Also from the servo comes a cable with a black and a gray wire enclosed which audiovox makes a big issue out of. Cut this cable off at the servo, and throw the six or seven feet of it away, as it's an obstacle only.
Also from the servo is a black ground wire. I shortened this and attached it to the bolt which holds the diagnostic center to the body. I then shortened the blue wire so it was the right length, and ran both these wires inside a piece of the supplied black conduit, and used a little black tape to make it all work and look right. The remaining wires from the servo, red, purple, yellow, green, and brown, all go together through the firewall. There's a nice round grommet that sets right beside the place where the factory throttle cable goes through. It's about the size of a 50-=cent piece. Pop it off, and on the back side you'll note it's held in by using a rectangular piece of rubber. Cut off about an eighth or quarter-inch of this rectangle, which will allow enough room to get the wires through the firewall and still re-use the factory grommet. There's a piece of some kind of material you need to punch through to get the wires inside, and it punched pretty easily with a screw-driver for me. Run all the wires inside. When you've pulled them all tight, go back to the engine compartment, pull about six inches back, and temporarily tape them all together using enough tape that they cant' escape back through the firewall, ensuring you'll have plenty of slack in your wiring harness, without getting too much.
I have a bad back, so had to remove the front seat to allow access to the rest of the job. Most limber folks don't have to.
Shorten the purple wire to length, and attach it to the green wire at the brake switch. Shorten the red wire to length, and attach it to the white wire with the green stripe at the brake switch.
The remaining wires from the servo, yellow, green, and brown, all hook into the same colored wires of the audiovox cruise control dash-mounted switch, so it's time to get prepared for this. If like my car, you've never had cruise control, on the far-left of the dash, right beside the instrument panel dimming control, there's a little black plate (at least it's black in my black interior), that covers the hole where the factory cruise on/off switch is located. Using a couple small screwdrivers, carefully pop this plate off. You can then, and I forget exactly how, release some type of clip mechanism wjhich gets you access to a wiring assembly located there. From under the dash, you can pull this set of wires to a place where you can see them, and put back together your cover plate, so if you ever want to return your car to stock, you have everything in one place. I took the two bolts out of the fuse assembly, and moved the fuse box out of the way, but don't know for sure if I had to or not. It was necessary to remove the bottom panel though which if I remember right was just two screws also.
You now have a hole in your dash which is too large to secure the audiovox cruise unit to. Take a piece of Styrofoam, and whittle it down to a size that is still larger than will fit easily into that hole. Styrofoam condenses and re-expands a little which makes for a nice tight fit. Because at a certain angle, I thought I might see a little foam, I painted my Styrofoam black, punched a small hole in the middle of it, and ran the yellow, green, brown, red, and black wires through it, and for now left it dangling. I cut the gray wire from the cruise switch off and threw it away, as it is also an obstacle.
I ran the black wire to the metal plate by the fuse box, and drilled a hole in the metal plate and used a screw to attach the black (ground) wire.
The orange wire which is changed to red after it leaves the fuse , and which I neglected to point out is separate from the other wires, was connected to the only yellow wire anywhere close to the fuse-box, by using one of the supplied blue wire connectors. I don't know what the yellow wire is for, but my test-light showed it only has juice when the ignition is on. I used a tie strap to secure the fuse close to all the other fuses, and ran the red wire through my Styrofoam.
The rest of the wireing was just using the two supplied computer-type plugs to fasten red to red, yellow to yellow, green to green, and brown to brown. (After cutting to appropriate lengths.)
At this point you may want to go for a joy-ride before fixing the cruise control switch. First, set your dip-switches inside the servo. Numbers 1,2, and 4, should be set "on". Numbers 3,5,6, and 7 are set "off". I've no idea why, as this is very counter to what audiovox recommends, but these settings are ideal as I learned from many many trial and errors. Also, I forgot to remove the little jumper wire inside the servo as audiovox recommends for all manual transmission autos, and mine works fine. One of these days I'm gonna take it off and see if that has an effect, but for now, my cruise control works perfectly…I do mean perfectly.
After making certain yours does as well, take an appropriately colored 100%
silicone, put a little on your Styrofoam and press it in place. Remove the paper
backing from your cruise control switch and put some silicone on there too.
Press it into place and secure with a lot of masking tape. Don't worry if you
aren't real neat as silicone is easily removed when dry. Let it set up over-night,
and remove the tape and clean things up. See how very nice the cruise looks
in this spot….almost like a factory design! Use some more of the provided black
wiring conduit to hold the wirings together under the hood, and finish off with
some black tape and black silicone to seal the ends, and enjoy your new cruise!
25 June, 2006