1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the Rostra 250-1223 Universal Electronic Cruise Control System. This system is designed to provide a convenient and consistent driving experience by maintaining a set vehicle speed.
Important Considerations:
- A compatible Rostra control switch is required and sold separately.
- Your vehicle must have an accessible mechanical throttle cable assembly for proper installation.
- For vehicles with manual transmissions, a clutch switch may be required and is sold separately.
- If your vehicle does not have a usable speed sense wire, Rostra part number 250-4165 may be necessary.
Image 1.1: The Rostra 250-1223 Universal Electronic Cruise Control unit, showing the main module, wiring harness, and various connection points. This image illustrates the primary components included in the system.
2. Setup and Installation
Proper installation is crucial for the safe and effective operation of your cruise control system. It is recommended to thoroughly read this manual and plan your installation before beginning.
2.1 Pre-Installation Checklist
- Ensure you have a compatible Rostra control switch.
- Verify your vehicle has a mechanical throttle cable.
- Gather necessary tools: multimeter, wire strippers, crimpers, drill, mounting hardware.
- Identify suitable mounting locations for the cruise control module and cable routing.
2.2 Mounting the Module
Select a secure, dry location under the hood, away from extreme heat or moving parts. Ensure the chosen location allows for optimal routing of the throttle cable to the throttle body without sharp bends or binding. Secure the module using appropriate hardware.
2.3 Throttle Cable Connection
Connect the cruise control's throttle cable to your vehicle's throttle body. Use the provided adapters as necessary to ensure a secure and smooth connection. Verify that the cable operates freely and does not impede normal throttle operation. Adjust cable slack to a minimum without causing tension at idle.
2.4 Electrical Connections
The Rostra 250-1223 system requires several electrical connections:
- Power (12V Constant): Connect the designated wire to a fused, constant 12-volt power source.
- Ignition (12V Switched): Connect the designated wire to a 12-volt source that is active when the ignition is on.
- Ground: Connect the ground wire to a reliable chassis ground point.
- Brake Switch: Connect to the vehicle's brake light switch. This connection is critical for disengaging the cruise control when the brakes are applied. Typically, two wires from the cruise control connect to the brake switch: one for constant 12V and one for 12V when brakes are applied.
- Speed Sensor: Connect to a reliable speed signal source from the vehicle. If a usable speed sense wire is not available, the Rostra 250-4165 speed sensor may be required.
- Control Switch: Connect the wiring harness from the cruise control module to your separately purchased Rostra control switch.
- Neutral Safety Switch (Manual Transmissions): For manual transmission vehicles, a connection to the neutral safety switch or a clutch switch (Rostra 250-4206, sold separately) is essential to disengage the cruise control when the clutch pedal is depressed or the transmission is shifted to neutral.
2.5 Dip Switch Settings
The cruise control module features internal dip switches to configure settings such as pulse count (PPM - Pulses Per Mile/Kilometer). Incorrect settings can lead to erratic operation, such as surging. Consult the specific instructions provided with your unit for the correct dip switch configuration based on your vehicle's speed signal output. Common settings include 4000 or 8000 PPM.
2.6 Post-Installation Testing
After installation, perform a thorough test drive in a safe environment. Verify that the cruise control engages, holds speed steadily, and disengages immediately when the brake pedal is pressed or the clutch is depressed (for manual transmissions). Adjust cable tension and dip switch settings as needed to achieve smooth operation.
3. Operating Instructions
Once installed and configured, operating the Rostra 250-1223 cruise control is straightforward using your compatible Rostra control switch.
3.1 Engaging Cruise Control
To engage the cruise control, accelerate to your desired speed (typically above 30 MPH or 50 KM/H, refer to your control switch manual for exact minimum speed). Press the 'SET' button on your control switch. The system will then maintain your current speed.
3.2 Adjusting Speed
- Accelerate: Press and hold the 'ACCEL' or 'RESUME' button to gradually increase speed. Release at the desired speed. A quick tap may increase speed by a small increment.
- Decelerate: Press and hold the 'COAST' or 'SET' button to gradually decrease speed. Release at the desired speed. A quick tap may decrease speed by a small increment.
3.3 Disengaging Cruise Control
The cruise control can be disengaged by:
- Tapping the brake pedal.
- Depressing the clutch pedal (manual transmissions).
- Pressing the 'OFF' or 'CANCEL' button on the control switch.
3.4 Resuming Set Speed
After disengaging, if you wish to return to the previously set speed, press the 'RESUME' button. The vehicle will accelerate or decelerate to the last set speed.
4. Maintenance
The Rostra 250-1223 Universal Electronic Cruise Control System is designed for long-term reliability with minimal maintenance. However, periodic checks can ensure optimal performance and longevity.
- Cable Inspection: Periodically inspect the throttle cable for any signs of fraying, binding, or excessive wear. Ensure it moves freely and is properly lubricated if necessary.
- Electrical Connections: Check all electrical connections for corrosion, looseness, or damage. Ensure wires are securely routed and protected from heat and abrasion.
- Module Cleanliness: Keep the cruise control module clean and free of excessive dirt or debris.
- Functionality Test: Regularly test the cruise control's engagement, speed adjustment, and disengagement functions to ensure proper operation.
5. Troubleshooting
If you experience issues with your Rostra 250-1223 cruise control, consult the following troubleshooting guide:
5.1 Cruise Control Does Not Engage
- Check Power: Verify that the module is receiving constant and switched 12V power, and that the ground connection is secure.
- Brake Switch: Ensure the brake switch connections are correct and the switch is functioning properly. The cruise control will not engage if it detects a brake signal.
- Speed Signal: Confirm that the speed sensor wire is correctly connected and providing an accurate signal to the module.
- Control Switch: Inspect the control switch and its wiring for any faults.
- Minimum Speed: Ensure you are attempting to engage the cruise control above the minimum operating speed (e.g., 30 MPH).
5.2 Cruise Control Surges or Does Not Hold Speed Steadily
- Throttle Cable Slack: Excessive slack in the throttle cable can cause surging. Adjust the cable to minimize slack without causing tension at idle.
- Dip Switch Settings: Incorrect pulse per mile (PPM) settings on the internal dip switches are a common cause of surging. Refer to the installation guide for the correct settings for your vehicle.
- Speed Signal Interference: Ensure the speed signal is clean and free from electrical interference.
5.3 Cruise Control Disengages Unexpectedly
- Brake Switch: A faulty or misadjusted brake switch can cause intermittent disengagement.
- Clutch Switch (Manual Transmissions): For manual vehicles, check the clutch switch connection and operation.
- Loose Connections: Inspect all electrical connections for looseness or intermittent contact.
If these steps do not resolve the issue, it is recommended to consult a qualified automotive technician or contact Rostra customer support.
6. Specifications
| Feature | Specification |
|---|---|
| Model Number | 250-1223 |
| Brand | Rostra |
| Connector Type | Plug-In |
| Contact Material | Silver |
| Contact Type | Normally Open |
| Mounting Type | Surface Mount |
| Operation Mode | Semi-Automatic |
| Number of Terminals | 3 |
| Item Weight | 3 pounds |
| Product Dimensions | 6 x 4 x 3 inches |
7. Warranty Information
Specific warranty terms and conditions for the Rostra 250-1223 Universal Electronic Cruise Control System are provided by the manufacturer. Please refer to the documentation included with your product or visit the official Rostra website for detailed warranty information.
8. Customer Support
For technical assistance, installation questions, or troubleshooting beyond the scope of this manual, please contact Rostra customer support. Contact information can typically be found on the official Rostra website or in the product packaging.
