When the Tire Pressure Monitoring System (TPMS) warns you that a tire is underinflated, the quickest way to identify the culprit is to use the car’s tire pressure readout if available. If your model doesn’t show per-tire readings, you’ll need to check each tire manually with a gauge.
Understanding the TPMS and tire pressures
The 2018 Honda Accord uses a TPMS to monitor air pressure in the four main tires. The system can alert you with a dashboard warning light and, on many trims, a tire pressure readout on the instrument cluster or driver information display. Some Accords display individual tire pressures (front left, front right, rear left, rear right) so you can see which tire is lowest. If your model doesn’t show per-tire pressures, you’ll need to compare readings manually with a gauge and the manufacturer’s recommended pressure.
To identify the low tire using the vehicle’s readout, follow these steps:
- Look for the TPMS warning light on the dashboard. If it’s illuminated, proceed to view the tire pressures on the driver information display or MID (multi-information display).
- Navigate to the tire pressure section of the display. On many 2018 Accords, you can access this through the INFO or VEHICLE menu and select Tire Pressure. The screen may show each tire’s current psi values (front-left, front-right, rear-left, rear-right).
- Note which tire shows the lowest pressure. That tire is the one that is low, or potentially the one that needs air first.
- Check for obvious causes around the low tire—nail or screw in the tread, puncture, valve stem issue, or a bead leak. If you spot damage, stop and address it safely.
If your specific Accord trim doesn’t display per-tire pressures, proceed with a manual check as described below and identify the low tire by comparing all four readings to the recommended spec.
Manual tire pressure check: how to confirm with a gauge
Before you start, gather a tire pressure gauge and locate the recommended cold-inflation pressures for your tire size. That information is printed on the driver’s door jamb placard and may also be in the owner’s manual. Note that pressures can vary by tire size and load, so use the value listed for your exact tires.
- Park on a level surface and ensure the tires are cool (ideally before driving or after a few hours of no use). Remove the valve cap from each tire.
- Place the gauge on the valve stem and take a reading for each tire. Record the numbers for comparison.
- Compare the readings to the door jamb placard values. The tire with a reading noticeably lower than the others (and below the recommended spec) is the low tire.
- Inflate the low tire to the recommended pressure, recheck after inflation, and replace the valve cap securely.
- Repeat the process for all tires, including the spare if you plan to rotate or replace, noting that the spare is often not monitored by TPMS on many vehicles.
A note on tire pressure: maintaining the correct cold-inflation pressure improves safety, fuel economy, and tire wear. After inflating to the proper pressure, the TPMS light should extinguish after a few driving cycles if there are no leaks. If the light remains on, there may be a slow leak or a sensor issue requiring professional service.
When to seek professional help
If you cannot locate a leak, notice persistent air loss, or the TPMS warning stays illuminated after inflating to spec, have the tires inspected by a tire shop or Honda dealership. A persistent TPMS fault can indicate a faulty sensor or a more complex issue with the TPMS system that needs diagnostic tools.
Summary
The Honda Accord 2018 uses TPMS to alert you when a tire is underinflated. If your model shows per-tire pressures on the dashboard, identify the low tire by reading the display. If not, manually check each tire with a gauge and compare to the recommended pressure from the door jamb placard. Inflate the low tire, recheck all tires, and monitor the TPMS to ensure the warning resets. When in doubt or if the warning persists after inflation, seek professional assistance to rule out leaks or sensor problems.