I would appreciate some help with finishing the installation of a Cruise Control (CC). I've gathered information from several threads, but seem to be missing a puzzle piece. I have installed R--tra Cruise Controls in a 57 T-Bird automatic and a 67 Corvette manual, so have some hands-on experience. I have a 1999 550 North American version. From the threads, I understand: - the needed components are 250-1223 in conjunction with one of the wand control switches (I chose 250-3304) and the much debated Clutch Disengagement Switch (250-4206) - the Steering Pump ECU (located in the passenger-side electrical panel) provides a Pulses Per Mile (PPM) signal at contact "V" (white wire) - PPM on the Cruise Control ECU should be set for 12,000 PPM - the ON dip-switches are 3, 5, 9, 10 and 12 - one of the F-Chat members assembled a kit some years ago, but I couldn't find the kit components. I don't know what was included in the custom wiring harness. The installed CC passes all the diagnostics referenced in the installation manual; however, will not hold speed after the SET button is pressed. It seems to engage and then disengage. If I set the PPM dip-switches from 12,000 PPM to 6,000 PPM, I see the same phenomenon as described in another thread where the car surges ahead when the CC is engaged and then drops off. Thanks in advance for your help.
Gain set to extra low PPK (pulses per kilometer) set to 7500 Engine/setup timer set to 8 cylinder high VSS (vehicle speed signal) source set to square wave input Transmission set to manual Control switch set to open circuit Dip switches are set for best use, do not change settings Dip Switch settings 3, 5, and 10, set to ON, all others set to OFF # 12 dip switch depends on control switch being used, open circuit set to OFF, closed circuit set to ON
The clutch switch is unnecessary as it requires a "resume" after every shift. CC should be used in the higher gears only. The tach wire (dark blue) connected to the car's tach will provide a safety if the clutch is depressed in the lower gears but this is not necessary if you never engage CC in the lower gears.
Hi Reese. That’s what I call a 1.000 dollar advice! Dave is a true gentleman. Willing to share this info. I bought a CC kit from him and I have really enjoyed it. Post a few pics and let us know if it works out for you.
Dave, Thanks for responding. I knew you were engaged with past threads and was hoping to get you engaged again. Clarification from your response: In order to set "Engine/setup timer set to 8 cylinder high" dip-switch 9 needs to set to ON, making the list of ON dip-switches 3 5 9 10 (and 12 for me due to the closed circuit control switch I selected 250-3304). These were my initial settings. After I failed to get the Cruise Control (CC) to respond on the road, I contacted technical support at thecruisecontrolstore where I purchased the CC. I spoke with Michael who reviewed my wiring. The CC manual indicates that if not used, the Dark Blue (Tach) feed "should" be grounded to avoid interference. The "should" is MUST. I made this change and then Michael ran me through a series of volt meter tests that produced OK results and then had me try a series of Pulse Per Mile (PPM) changes with the results I described in my original post. At the end of yesterday: - Michael indicated that the CC ECU was expecting to get a VSS signal voltage between 6+ and 12+. He when off to search his sources on locating VSS signal information on the 550. - My to-do: Check the VSS wire voltage. When I installed the CC ECU, I inserted cable connectors so that the CC ECU could be removed to access other engine bay parts for maintenance. I tapped into the VSS gray wire at the CC ECU connector and found that with the ignition switch on (engine off) the VSS gray wire voltage was 6.37. With the engine running and the car stopped, the voltage is 9.32; however, when the car is moving the voltage is 4.67 (below the 6+ volt requirement). I suspect this is the problem. Perhaps I have a faulty connection from the gray VSS wire to the Power Steering ECU white wire? Are there available specs on the voltage(s) provided to the Power Steering ECU from the VSS wire? I'd hate to bother with a re-connection when the voltages I'm seeing are within spec. And if this is the case, why is this model CC working on other 550s? Is there another location where I can tap into this VSS source? From the 550 Maranello Workshop Manual Vol 2, the Hydraulic Power Steering ECU is listed as Item 159. I can't locate this on any of the wiring diagrams. The VSS input wire into the Power Steering ECU must have a source. Is there another more complete wiring description (diagram) than what's provided in the Workshop Manual? Thanks again for your help
At first I followed Rostra's tech info for "engine setup timer" then I tried different settings and 8 cylinder low seemed to be the smoothest although tapping "Accelerate" gives a bit less than one MPH increase. There are 5 CC's that have been running with these settings for four years now and everyone likes them. Carl and I think it's smoother than factory CC's in our other cars. I used the "V" terminal on the steering ECU for the speed signal. Since I was doing this for others I tapped into the actual ECU with a pigtail, not the wiring from the socket so I don't know what color the socket wires are. Be sure you have 1/8 inch slack at the throttle cable. I have not been able to find any wiring diagram relating to the steering ECU either. My remark about "engine timer set to 8 cylinder high" is wrong, I wrote that before I changed to 8 cylinder low. I just checked my settings and 3, 5, and 10 ON is correct. ( actually I changed my switch a week ago to a closed circuit switch and wired the Rostra dark blue tach wire to the 550's Tach as a safety feature. It works by disconnecting the CC if it senses a sudden increase of 1,000 RPM. )
I just checked a you are correct with the white wire on the Steering ECU socket. I don't know why you are having problems, the only thing I can suggest is to check continuity on everything. I would also eliminate the clutch switch. Are you sure you have the brake switch wires correct, Ferrari's wiring is counterintuitive. On the Ferrari Blue is the positive 12VDC at the brake switch.
OK, I made the change to have 3-5-10-12 set to ON. Seems to engage and then drops off (will not hold speed). The same result as with 3-5-9-10-12 set to ON. Based on what I've read in other posts, none of the working CCs use the Clutch Disengagement Switch. I have this working on another car, but will remove it from the circuit to eliminate a failure point (or incorrectly implemented wiring on my part even though the multi-meter produces expected results). 1) Where did you connect the Dark Blue wire to the Tach (location and wire color)? This seems like a logical replacement for the clutch disengagement switch. 2) You indicated that you pig-tailed onto the "V" terminal on the Steering ECU. Did you A) wrap the gray wire around the ECU terminal, B) remove the ECU from its socket, stick the gray wire into the "V" terminal socket slot and reinstall the ECU or C) solder to the terminal. If you did solder, did you worry about heat damaging the ECU? Thanks again for your guidance
To the brown/black wire in the back of the Tachometer. (requires removing the binnacle) I opened the ECU by removing the cover and soldered a pigtail to the "V" terminal then ran the pigtail out through a hole in the cover It must be said that I didn't use any of the parts in the Rostra kit other than the CC module/cable and the wires which I only used as raw material. I shortened the cable, made bespoke cable mounting and connecting parts, and a custom wire harness. Did you verify the connection at the brake switch?
OK, I removed the Clutch Disengagement Switch from the circuit. I verified that the CC Red Brake Positive wire is connected to the +12 Volt hot side of the brake switch. The connector on the brake switch has 3 terminals, but only 2 are used. The Blue wire on the Brake Switch is hot (+12 Volts). The other used terminal has 2 Red wires connected and these are Ground. This is where I connected the CC Violet wire. The 3rd Brake Switch terminal is empty. When the ignition key is ON and the brake pedal is pressed, the brake lights are on and the CC Violet wire reads +12 Volts. When the brake pedal is released, the brake lights are off and the CC Violet wire reads 0 volts. I retested the car with the same result, the CC will not maintain a set speed. Tomorrow, I'll remove a working CC from one of my other cars and see if it works in the 550. I'll need to cut the wiring harness and add the same configuration snap-connectors that I have installed on the 550, so it will be plug-and-play. If the borrowed CC works on the 550 then the CC module is faulty and I'll request a replacement. If it doesn't, then it's my faulty wiring and I'll really start scratching my head. I'll report my findings. Thanks again for supporting this challenge.
OK, I'm really scratching my head on this. Maybe, just maybe, but to cover all bases, can you manually retract the cable to open the throttles without too much force? Do you have 1/8 inch slack? Do you have LED brake lights? I have spent at least ten hours trying to get the orange ENO wire to work as it should. Rostra tech has been no help. I'm not a novice at this and that wire will not "pull low" to quote Rostra. Rather it is open under all circumstances. Keep the faith, somehow we'll get this working.
Not to worry --- this is a challenge, not a problem! My grandfather was a mechanic and said: If it can't talk back to you, you should be able to out-smart it.
AGREED! I can't thank Dave enough for building the MSW CC. It is slick and better than some OEM systems I have used. I got a new project for Dave. We need memory for our driver's seat. I think if we had programed reversing of the seat base and then 1 button press replacement of the seat base to driving position our rear ends would not bang into and wear out the driver's left seat bolster. What do you think?
View attachment 2694567 I spent today trying to power a small instrument light, the same one used in the 55o instrument panel, with a 5 pin relay like the one shown in a Rostra instruction page. I used the orange ENO wire to engage the relay to send 12VDC to the lamp. It did not work. I checked continuity from the CC module to the relay and have good continuity. This is the same results I got two years ago when I tried this The reason I want that ENO wire to work is that I spent a lot of time figuring out how to have a cruise control icon on the dash warning panel . Here is the result, and I'm really proud of it!!
BACK ON TOPIC: Dave, I was swapping the working CC in one of my other cars with the one I got for the 550 and noticed that the 550 connecting probe (dr gray plastic stalk where the inner cable core attaches to the CC ECU) was wobbly loose. After talking with the vendor's tech, I removed the cover of the CC and removed the circuit board. Hidden below the circuit board is a motor belt driven screw that runs through the plastic stalk. The stalk has a foam pad mounted between the base of the stalk and the outer CC case. On the back side of the stalk is a metal cover that touches the motor that controls the screw shaft. I suspect that during power on, an electro-magnet produces the pull on the CC cable. I reset the stalk to where it was fully extended with the foam pad holding it against the outer cover. I test drove the car and the CC still will not hold a set speed. I then removed the CC from a working car and installed it into the 550. Same result - the CC won't hold a set speed. I believe that the CC magnet is not strong enough to hold/move the throttle. I know you said you shortened the CC cable and made your own wiring harness. WHERE DO DO THE WORKING CCs HAVE THEIR CABLEs ATTACHED TO THE THROTTLE? Thanks again.
Reese, PM me your email address and I'll send you my installation instructions. It's too big to post here.
Hi Dave. Is it possible for me to get that green CC icon on the dash? How do I do it? Looks good for sure!
Erik, It's really complicated. you have to take the warning cluster out of binnacle, cut out the unused icon in the lower right corner, then find a CC icon on some other dashboard. I used ford dash I found on ebay. Then you have to tap into the wires to the LED (black and light blue) on the CC switch and run them to the light in the binnacle. https://www.ebay.com/itm/04-08-Ford-F150-Speedometer-overlay-gauge-face-Gauge-Face-/262295848250?hash=item3d120d053a
Still unable to get the Rostra CC to function on my 550. Dave, thanks for your installation instructions. Our approaches for throttle linkage and CC ECU location are similar. Since my last post, I've been working with Michael Fox (M & R Auto Electronics that is the Sales & Support side of Rostra). After more than several scenarios, it appears that the VSS signal from the Servtronic Steering ECU is not providing an adequate signal for the CC to function. Michael loaned me a stand-alone VSS signal generator to verify that the mechanical side of the CC would pull the throttle; and it does. I've also installed a Rostra 250-4369 signal divider (used on Chryslers to reduce the number of pulses, but also produces a "cleaner" output signal, which is what I was hoping would solve the issue) - still NO GO. I would hate to have to install a separate VSS sensor on one of the rear axles and use the magnet pickup offered as an option by Rostra. The yellow-white VSS input to the Servtronic (pole "V") must be coming from the speedometer ECU and each of the wheels must be producing a VSS for the ABS. Any ideas appreciated.
OK, well, this is frustrating. I doubt it's a VSS problem since I have 5 units working with that input from the steering ECU. I confirm that the yellow/white wire is the VSS signal at the steering ECU. I'm going to ask a question that may sound insulting, especially since you have done other installations but here goes........ Are you absolutely positively sure about the dip switch settings? I ask because on mine it is almost impossible to see clearly in there because of the hood strut. I just took mine for a test drive trying to replicate your problem by engaging CC with the brake pedal slightly depressed but it simply would not engage at all. About the only thing I can think of is a binding throttle cable, just enough that the CC can't overcome so it disengages.
SUCCESS - There was too much resistance in the ground circuit. After several months of intermittent work on installing/configuring a Rostra 250-1223 Universal Curise Control (CC), it's now working. Thanks to ferraridriver (Dave) for all the support. After many phone calls with M&R Auto Electronics (Rostra's performance support), I arranged time with their shop and drove the 10 hours to Saginaw, MI where we isolated the issue within an hour. My right foot and leg were a lot happier on the return trip. Although we had performed continuity checks on all the circuits, we had not checked the resistance. If the resistance on the ground circuit is above 2.5 ohms, the CC will engage but immediately disengage. I had the ground wire attached to one of the bolts holding the power steering reservoir to it's mounting bracket (2.95 ohms measured). The ground wire mounting location was moved to one of the mounting studs that holds the reservoir mounting bracket to the brake master cylinder housing and now measures 0 ohms resistance.
