GRUNDIG 550S Solar Powered TPMS for RVs & Trucks, 6–36 Wheel Monitoring, 200 PSI, Real-Time Tire Pressure & Temp Alerts

Choose based on your vehicle’s total wheel count: 6 wheels for small campervans/single-axle trailers, 8 wheels for dual-axle RVs, 22 wheels for heavy-duty trucks with trailer, 36 wheels for commercial multi-axle rigs. All configurations use the same 200 PSI external sensors and support solar + Type-C charging.

The sensors only transmit when they detect a pressure change greater than 1 PSI. When the vehicle is stationary, the monitor automatically enters sleep mode after 3-5 minutes and the displayed values may freeze. This is normal behavior. The display will refresh once the vehicle is started and the sensors detect vibration or pressure change. If you need real-time readings while parked, briefly press any button to wake the monitor.

Yes. The monitor supports PSI, BAR, °C, and °F units. To switch: long-press the SET button to enter the parameter setting menu, navigate to “Unit” using the +/- keys, then press SET to toggle between BAR/PSI and °C/°F. Hold SET to save and exit.

The 550S supports 6, 8, 22, or 36 wheel positions depending on your purchased configuration. To pair a new sensor: (1) Power on the monitor first; (2) Long-press the “Matching” button to enter pairing mode; (3) Hold the corresponding “+/-” key to select the wheel position; (4) Screw on the external sensor to the tire valve - it will transmit a unique ID code; (5) When the ID appears on screen, press SET to confirm. The pairing is complete when the tire position lights up.

The 550S features digital “Tire Position Exchange” - you don’t need to unmount the sensors. After physically rotating tires: (1) Long-press SET to enter settings; (2) Navigate to “Interchange tire setting”; (3) Select the source position number and press SET; (4) Use +/- to choose the target position; (5) Press SET to confirm and HOLD to save. You can swap multiple positions before saving.

Default values are: 6/8-wheel version: High 116 PSI / Low 58 PSI / Temp 65°C (149°F); 36-wheel version: High 175 PSI / Low 100 PSI / Temp 70°C (158°F). Maximum settable pressure: 199 PSI (13.7 BAR). Minimum settable pressure: user-defined. We recommend setting thresholds based on the tire manufacturer’s recommended cold inflation pressure (typically 80-110 PSI for RVs, 100-120 PSI for commercial trucks).

The 550S system provides comprehensive safety alarms: (1) High Pressure - flashes high pressure indicator with audio beep; (2) Low Pressure - triggers low pressure warning; (3) High Temperature - alerts when thermal limits are exceeded; (4) Slow Leak - alerts during gradual pressure loss; (5) Fast Leak - urgent pattern for rapid air loss; (6) Sensor Low Battery - flashes when sensor battery drops below 2.2V; (7) Sensor Fault - indicates signal loss or sensor failure. Press any button to silence alarms.

First, drive the vehicle for a few minutes - the sensor will wake up and re-transmit when it detects pressure change or vibration. If the issue persists: (1) Check the sensor battery (replace CR1632 if low); (2) Verify the sensor is properly tightened on the valve; (3) For long trailers, ensure the signal booster is installed near the middle of the vehicle; (4) As a last resort, unscrew the sensor, wait 1 minute, and reinstall to force re-pairing.

Each sensor uses a standard CR1632 coin cell battery with approximately 2-year lifespan under normal use. To replace: (1) Unscrew the sensor from the tire valve; (2) Use the included battery wrench to unscrew the sensor housing; (3) Remove the old CR1632 battery; (4) Insert a new CR1632 with the positive (+) side facing up; (5) Reassemble and reinstall. The monitor will alert you when a sensor’s voltage drops below 2.2V.

The 550S uses a heat-resistant 1800 mAh lithium battery designed for automotive environments. However, for optimal performance: (1) In summer, mount the display in a shaded area or use the windshield bracket to avoid direct sunlight; (2) Below -20°C, the display refresh will slow down but resumes normal operation at warmer temperatures; (3) In extreme heat (>65°C), the display will automatically enter protection mode and resume when temperatures normalize.

The signal booster (repeater) strengthens the 433.92 MHz wireless signal from sensors to the monitor. It is included with 22-wheel and 36-wheel configurations, and optional for 6/8-wheel setups. We strongly recommend it for: (1) Vehicles longer than 10 meters; (2) RVs with metal-bodied trailers; (3) Commercial rigs with multiple axles. Installation: connect the booster’s red wire to ACC power and black wire to ground, mount near the center of the vehicle. The booster’s LED should flash red during normal operation.

All GRUNDIG 550S systems come with a 2-year manufacturer warranty covering defects in materials and workmanship under normal use. The warranty does NOT cover: (1) Damage from improper installation or self-disassembly; (2) Normal wear of CR1632 sensor batteries; (3) Damage from accidents, water immersion beyond IP67 rating, or use outside specified operating ranges. For support, please contact your local distributor with your order number and a description of the issue.