Why The Tire Pressure Warning System Light In Your Ford F-150 Is On and How To Make It Go Out
Tire pressure monitoring systems are government-mandated in America. This is not a feature that Ford installs as a feature on just some trims. For more than a decade, Ford has been installing systems and they have been driving some Ford F-150 owners crazy. They certainly do help let you know if a tire is deflated. However, in many cases, the system can be an annoyance.
Here are the reasons that your Ford F-150 has a “Tire Pressure Monitoring System” alert. We will refer to it as “TPMS” from here forward. Before we begin, if your TPMS system warning light is on now, immediately check your tire pressure. Some vehicles can display the pressure in the information display. If your Ford F-150 doesn’t, use a tire pressure gauge to check the pressures. The correct setpoints for your Ford F-150 are listed on the driver’s door. Do not drive your Ford F-150 with the TPMS light on without verifying that the tires have proper air pressure.
F-150 Tire Pressure Warning - Temperatures Have Dropped
If seasonal temperatures are dropping and your TPMS warning light is illuminated, the reason is most likely due to the temperature difference between when the pressure was last set and the current temperatures. The pressure inside of a tire drops with temperature. You need to reset the tire pressure in early winter and also early summer. The air didn’t leak out of your tires. It simply became lower in pressure as the temperatures dropped. This happens to all tires, in all vehicles, regardless of which gas is inside of them (air or nitrogen).
Ford's manual notes, "If the vehicle is stationary overnight with the outside temperature significantly lower than the daytime temperature, the tire pressure may decrease about 3 psi (21 kPa) for a drop of 30°F (17°C) in ambient temperature. This lower pressure value may be detected by the tire pressure monitoring system as being significantly lower than the recommended inflation pressure and activate the system warning light for low tire pressure."
If you find that the pressure inside your tires is lower than the setpoint, top them off to the correct pressure. The TPMS light should go out shortly after you set the pressures to the proper level. If just one tire is lower than the rest by more than around 30%, have a tire technician investigate.
F-150 Tire Pressure Warning - You Have a Flat Or More Than One Flat
The reason you have a tire pressure monitoring system in your Ford F-150 is to detect a flat tire. Or more than one flat tire. If the light comes on while you are driving, this is the likely reason for it. Pull off the road to a safe area as quickly as you safely can to investigate. A quick visual inspection is not enough. Use a tire gauge to check the pressure in all four tires. If you have a flat, refer to the Ford F-150’s owner’s manual (see below) on what to do.
F-150 Tire Pressure Warning - TPMS System Failure
Ford’s TMPS indicator can tell you if there is a problem with the system itself. Ford’s manual reads, “Your vehicle has also been equipped with a TPMS malfunction indicator to indicate when the system is not operating properly. The TPMS malfunction indicator is combined with the low tire pressure telltale. When the system detects a malfunction, the telltale will flash for approximately one minute and then remain continuously illuminated. This sequence will continue upon subsequent vehicle start-ups as long as the malfunction exists.”
If you have verified that the pressure in your tires is correct using a tire gauge, and the TPMS system is displaying a warning, ask a mechanic for help. You don’t have to go to a Ford dealer, but if your Ford F-150 is under the initial new vehicle warranty, that would certainly make sense.
Like any system in your Ford F-150, age and damage can cause a problem with the TPMS system. Individual sensors in the tires can be replaced, but the system will still need to be re-initialized. We suggest that this job is best done by a mechanic or tire professional who understands the system and can handle the work, but you can a try at it with the manual.
F-150 Tire Pressure Warning - Tire Sealants
In the owner’s manual, Ford warns that emergency tire sealants like Fix-A -Flat, or Slime may cause your TPMS sensor to malfunction. The warning says, “Only use tire sealants in roadside emergencies as they may cause damage to the tire pressure monitoring system sensor.”
Here is what the Fix-A-Flat brand says about TPMS sensors and its product: “Fix-a-Flat is tire sensor safe. After the qualified tire repair professional has repaired your tire, they should clean the TPMS device with water to remove any sealant that may have come into contact with the device. After the repaired tire is replaced and inflated, the TPMS system can be reset and will resume operating as normal.”
F-150 Tire Pressure Warning - New Tire Or New Tires
If you buy new tires for your Ford F-150 and immediately get a tire pressure warning light, check the pressure. Mistakes can happen. Flats sometimes happen driving out of a tire shop parking lot. If you have checked the pressure and it is properly set, return to the tire shop and let them know that the Ford F-150’s TPWS system has indicated a problem. If the shop changed the valve stems in the tires, the system may need to be re-initialized.
Be aware that some TPMS systems are sensitive to tire sizes. You should only use the exact size of tire your Ford F-150 came with. If you have mounted aftermarket wheels or a different size tire, the retailer who did the work should be able to explain to you how they will resolve the TPMS system errors.
F-150 Tire Pressure Warning - Nitrogen Is Unnecessary
There are some dealers and shops that suggest nitrogen as a solution to a TPMS problem in a Ford F-150. The claims that these advocates of nitrogen for tires make are unfounded by science (the author’s degree is in mechanical engineering).
Furthermore, your Ford F-150 was designed to work perfectly fine using compressed air. Does inflating an underinflated tire with nitrogen cause the TPMS light to go out? Of course it might. Just as inflating the tire with compressed air will do. If you wish to spend money on nitrogen, that is your call. Just know that the Ford F-150 doesn’t need it.
A TPMS system alert is always an annoyance, but for the most part, it is a feature that is intended to help us in case a dangerous situation develops. Add air to your Ford F-150’s tires when temperatures begin to drop in early winter. Reset the pressures again in early summer. These are the best two habits you can have to avoid TPMS issues in your Ford F-150.
Resources Guide: Ford F-150 Owners Manuals
Ford F-150 Tire Pressure Frequently Asked Questions:
Q: How do you reset the TPMS light on a Ford F-150?
A: Use the owners manual link at the bottom of the story to find your Ford F-150’s year and instructions. Follow them, but be aware that resting the system may not solve the underlying issue.
Q: Can the TPMS be in the Ford F-150 turned off??
It cannot be turned off. It can be reset.
Q: Is it dangerous to drive with the tire pressure light on?
A: Yes, driving without knowing why the light is on is dangerous until you have checked the pressure with a tire pressure gauge to verify that the pressures are correctly set.