RV TPMS not reading? Here's how to fix it.
A flashing or blank TPMS sensor is usually a battery, a pairing issue, or the booster. Walk through it.
A working tire pressure monitor (TPMS) is the single best safety upgrade for any RV. A blowout at highway speed can total a rig, and TPMS gives you a 30-second warning before it happens. But aftermarket RV TPMS systems (TST, TireMinder, EEZ TIRE, Tire Linc) are notoriously finicky. Sensors disappear, batteries die, and the monitor shows dashes instead of pressure. Here's how to get them working again.
1. Check the sensor batteries
Most RV TPMS sensors run on a CR1632 or CR1632 coin cell battery that lasts 1-2 years. When the battery dies, the sensor goes silent and the monitor shows dashes. Unscrew the suspect sensor (it threads onto the valve stem like a tire cap), pop the cover, and replace the battery. The sensor will rebroadcast within 30 seconds.
2. Confirm the monitor is paired with each sensor
Each sensor has a unique ID that the monitor learns during pairing. If a sensor was replaced or the monitor was reset, the pairing is lost. Check the monitor's setup menu, you should see 6 sensor IDs (or however many tires you have). Re-pair any missing sensors using your monitor's pairing procedure (usually hold a button while installing the sensor on the stem).
3. Use the signal booster (long rigs)
Class A motorhomes and 5th wheels are long enough that the TPMS radio signal can't reach all the way back to the rear tires. Most kits include a signal booster (a small puck that plugs into a 12V outlet) that retransmits the signal. If your kit came with one, install it in the middle of the rig. If not, your kit may be too short for the rig.
4. Re-seat the sensor on the stem
Sensors with metal valve stems sometimes lose contact when grit gets in the threads. Unscrew the sensor, blow out the valve stem with compressed air, and screw the sensor back on snug. Check for air leaks with a soapy water bubble test, the sensor should not leak air around the threads.
5. Replace the rubber valve stem
Cheap TPM sensors weigh more than the original valve cap, and over time they fatigue rubber valve stems. A failed rubber stem can either leak air or break off entirely (this is bad at highway speed). Upgrade to metal valve stems whenever you mount a TPMS, this is the right way.
6. When in doubt, send it back
If your monitor still won't read after fresh batteries, re-pairing, and a booster, contact the manufacturer. TST, TireMinder, and EEZ TIRE all have responsive customer service and will replace sensors under warranty. They know their products are finicky.
Still stuck?
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Open CamphostFrequently asked questions
How long do RV TPMS sensor batteries last?
1-2 years on average. Cold weather drains them faster. Most sensors use a CR1632 coin cell, the same battery in many car key fobs. Keep a 4-pack in the rig.
Do I need TPMS on a travel trailer?
It's the single best safety upgrade you can buy. A trailer tire blowout is harder to feel from the tow vehicle than a tow vehicle blowout, and the damage from a flailing tread is severe. Yes, get one.
Why doesn't my TPMS show pressure for one tire?
Either the sensor battery died, the sensor lost pairing, or the signal isn't reaching the monitor (long rigs without a booster). Walk through the troubleshooting steps in order.
Are aftermarket RV TPMS kits accurate?
Within +/- 2 PSI for most kits. Don't rely on the absolute reading for critical decisions, set your inflation with a quality gauge and use TPMS to monitor changes from baseline. A sudden 10 PSI drop means something is wrong, regardless of the absolute number.