Rostra Precision Controls, Inc. Frequently Asked Questions

Does the cruise control kit come with everything I need?

The majority of Rostra-manufactured cruise controls systems are sold as complete kits. As well, Rostra manufactures universal cruise control units that often require the purchase of additional pieces to function with certain vehicles including vehicle speed signal (VSS) generators and control switches. To get a listing of exactly what parts will be necessary for your vehicle, please use the Vehicle Search menu at the top of the page or download our yearly catalog. If you have questions about a customized cruise kit, feel free to call our customer service department at (800) 782-3379.

Where are the programming switches?

The programming switches are located under the black rubber grommet on top of the cruise module. (See images below)

Where is the LED?

The LED is a surface-mount light on the circuit board to the left of switch number ONE of the programming switches.

LED is staying on during test procedure.

If the LED stays on during the self-diagnostic test, you have a poor ground on the black wire (main ground) of the unit, or violet wire (cold side of the brake switch). As well, switch TWELVE of the programming switches could be in the wrong position.

LED will not come on during test procedure.

If the LED light does not turn on during self-diagnostic testing, there is a power related problem. Check the red wire (hot side of the brake switch) for +12-volt constant power, or brown wire (accessory power) for +12-volts when key is on.

What is Gain (sensitivity)?

Gain is how the cruise control reacts to road conditions and engine size. Always start at the factory setting which is mid-gain. If the vehicle surges while the cruise is engaged, you will need to adjust the gain setting. A fast surge, when the vehicle speeds up rapdily above the cruising speed, requires the gain to be lowered. Set the gain to low or extra-low if needed. A slow surge, where the vehicle slows well below the cruising speed, rquires the gain to be raised to high.

What is Engine/Setup Timer?

Engine/Setup Timer is how fast the cruise control retracts the cable once the cruise is set. Always start at Low. If the vehicle drops below the set cruising speed, but then recovers. Set to High or Extra-high if still not acceptable.

Note:

The use of LED tail lights requires a five-function automotive relay to bypass the brake system. LED tail lights do not let the violet wire (cold side of the brake switch) see ground through the brake lights, themselves. Wiring in a relay is as follows:

Note:

All settings are based on 1/8-inch slack in cruise control cable. More slack will cause the cruise control to surge or lose speed once set.

Will a steering wheel-mounted switch work on my vehicle?

RF switches can be installed on several vehicles, but are not recommended for every vehicle. To find out if your vehicle has an RF switch available, check out our application guide.

What are my options for acquiring cruise installation information?

Located on this website, you will find both application and VSS/TACH information. We offer all of our installation manuals for download, but you can also fax your question to (910) 276-1354.

What if my vehicle is not listed?

Have no fear! Just because your vehicle is not listed in our application guide doesn't necessarily mean we don't offer a cruise control kit for it. Call our customer service department at (800) 782-3379 for specific application questions.