This wireless electronic tire pressure monitoring system can raise your comfort level while RVing.
By Bill Hendrix, F761S
April 2007
During our many years of extensive motorhome traveling, potential tire problems were always a nagging concern. We try to stop about every two hours to perform a visual exam of the towing equipment and the tires, but this really doesn’t help much if a tire is deflating in between stops. A few years ago a tag axle tire on our motorhome picked up a piece of metal, and the tire was ruined before we knew a problem existed. The expense is considerable, but the loss of time can be a major inconvenience, especially if a tire must be shipped to a not-so-convenient location. The tires on the towed car were a major concern as well, as extensive damage or even a fire can result from an undetected flat.
Many of us have had less than satisfactory results from the prior generations of tire pressure monitoring equipment, but like many products, a course of evolution and competitive pressure has improved these products. While at the FMCA convention in Pomona, California, in 2006, I listened to an explanation of the features of the PressurePro tire monitoring system, a highly refined product manufactured by Advantage PressurePro of Harrisonville, Missouri.
PressurePro is a wireless electronic system composed of two components: tire pressure sensors that screw onto the valve stem of each tire (one sensor per tire) and a monitor that displays the various pressure readings of the sensors. The system also comes with a power cord, an antenna, hook-and-loop fastening pads for mounting, and full instructions. Each sensor is a battery-operated radio frequency transmitter that uses an advanced technology to send a very short burst of digital data to the monitor.
When the sensor is installed, using the procedure outlined in the installation instructions, it remembers the base tire pressure at the time of installation, as well as its location on the vehicle. It will check the tire pressure every seven seconds and report a normal “check-in” status to the monitor every five minutes. The status report will update the current tire pressure to the monitor’s memory but will not display that pressure unless you scroll through the various tire locations with the display’s controls.
If a 5-minute status report is not received by the monitor, the location indicator on the monitor illuminates. It will remain illuminated until a status report is received. If the tire pressure drops 12.5 percent below the base pressure, an immediate and constant warning is sent to the monitor as a first-stage alert “” displaying the pressure, flashing the tire location, and beeping once every second. If the tire pressure drops 25 percent below the base, the monitor will beep and flash twice per second.
Each sensor is approximately 1 inch in diameter and weighs only 2/3-ounce, so rebalancing of the tires should not be necessary. Locking devices are available as an option. The transmitting frequency is FCC-approved 433.92 MHz FM with a line-of-sight range of approximately 100 feet.
For larger motorhomes towing a vehicle, reports from the towed vehicle tire sensors may be marginal, because of the huge mass of material between the car and the monitor. PressurePro has two remedies for this situation: a remote antenna that replaces the one mounted on the monitor, and a repeater. The repeater is a combination receiver and transmitter that can be mounted anywhere 12-volt power is available. Placing the repeater in the rear of the motorhome should give better reception from the sensors on the towed car as well as those on the rear wheels of the motorhome. These signals are then transmitted to the monitor, thus shortening the reception distance and improving reliability.
Duane Sprague of L&S Safety Solutions LLC (800-521-6820; www.tirepressuremonitor.com), a North American distributor for PressurePro, arranged for a system to be installed on our motorhome and towed car while we were in Pomona for the convention. He also furnished a remote antenna and a repeater. He led me through the installation and thoroughly explained how the system operates.
After installing the sensors, one at a time on the motorhome and car, making the locations register to the monitor, and testing the system, I selected a temporary location for the monitor. Initially, we did not install the remote antenna or repeater so we could see how the basic system would receive data from the car’s sensors with the 3½-inch monitor-mounted antenna. With everything checked out and working, we departed California and headed toward Colorado.
During the first day of travel, the right rear sensor on the car occasionally would fail to “check in” and that location would illuminate on the monitor. A few minutes later, the light would go out, indicating a subsequent “check-in” was accomplished. Radio frequency signals have the ability to bounce or reflect, so passing vehicles and objects along the roadway will actually improve reception.
Midmorning on the second day, we got a low-pressure alert from the right rear tire on the car indicating 28 psi. The manual does caution that radio frequency (RF) interference is always possible, but with serialized identification of each sensor, RF interference and cross-talk have been highly minimized. My first thought was that of a doubting Thomas. This just had to be a false alarm, but I pulled over at the next opportunity and went back to see what the problem might be. The tire looked a little low so I unscrewed the sensor and checked the pressure. It should have been 34 psi but was down to 26 psi, and I found a nail in the tread. After repair we were on our way again, without any damage.
That evening I installed the remote antenna but did not see any significant improvement in reception. This could have been because the two locations I tried may not have been appropriate. Before departing Colorado for our Vermont destination, I removed the remote antenna and installed the repeater in the rear of the coach. With the repeater operating, we received only one failed “check-in” during the trip. One time we did get a false alarm, but the pressure displayed on the monitor was not a low tire but a normal tire pressure. Apparently, this was genuine RF interference. I turned the system off and then back on. Within a few minutes, all the sensors checked in normally.
To display the tire pressures at any time, just use the up or down buttons to scroll through the tire locations. This feature is very convenient for checking the tires each morning. The transmitter specifications state the pressure to be accurate to 5 percent, but most are within 2 percent.
Four different monitors are available that will accommodate virtually any vehicle or combination of vehicles from four to 34 tires. The monitor measures 6½ inches by 3 inches by ½-inch, is very lightweight, and can be positioned anywhere in the driver’s field of view. The current price of the monitor is $190 and each sensor is $50. The system is relatively easy to install and can be moved from one vehicle to another with no hassle. The company claims the batteries in the sensors have an expected life of about 3 years. When not in use, the sensors may be removed to extend battery life. (If doing so, mark the location of each sensor, as they must be put back on the same tire; otherwise, the installation procedure will have to be repeated.) When new batteries are needed, the company will exchange the sensors for just the price of the battery, expected to be about $25 each. Each system comes with a one-year limited warranty.
So far, the PressurePro system has performed as represented and I feel a better comfort level, especially with the towed car. More information, including locations of distributors such as L&S Safety Solutions LLC, is available at the manufacturer’s Web site “” www.advantagepressurepro.com “” or by calling (800) 959-3505.
PressurePro With The Crossfire System
If your duals are equipped with the Crossfire dual tire pressure equalization system from Dual Dynamics, a modified air hose must be used in order to be able to attach a PressurePro sensor to each of the dual tires. For about $40 Crossfire will send you a pair of hoses that have been fitted with an extra valve stem to be used on the inside dual. Without the second sensor on the Crossfire system, a low-pressure alarm would be sent only in the event of deflation of the outside dual. To ensure a proper fit, measure the existing hoses before ordering their replacement. After installation, reinflate the duals to the proper pressure, as some air will be lost in the process. When installing the sensors, be sure to identify the inside and outside positions correctly on the monitor.
For more information, visit www.dualdynamics.com or call (800) 228-0394.