Tire Pressure Light coming on

The Tire Pressure Light is coming on.
Experienced mechanics share their insights in answering this question :
The Tire Pressure Light comes on when the air in the tire is low. If you have tested the tire pressure and it is normal, but the Tire Pressure Light remains on, you need to have the TPMS system checked with a specific scan tool to determine which sensor is bad, and have it replaced. I would recommend taking the car to the tire shop that has a TPMS scan tool, and have them replace the bad sensor.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Restart the car tire pressure sensor

It is time to check the sensor system for sure. This test is done by resetting the system. Depending on the type of car tire pressure sensor, the reset button will appear in its original positions. Usually, the position under the steering wheel will be for the reset button.

The TPMS light indicates that one or more of your tires on your Subaru is low on pressure. This might be a result of a puncture or a leak, or it could just the result of a big swing in the outside temperature.
When the TPMS warning light comes ON and stays ON, this indicates a low tire pressure condition in one or more tires. Inflating the tire to the recommended tire pressure found on the door placard should cause the light to turn OFF.
The problem could be a damaged or shorted antenna near the wheel, or a wiring fault between the antenna and the module. If you suspect the TPMS module is not receiving a good signal from one or more sensors, check the antenna wiring for continuity and problems such as shorts, opens or high resistance.
Most TPMS sensors run on batteries that are built into the sensor and these batteries are not replaceable. The life expectancy of the lithium ion batteries in a TPMS sensor is anywhere from 5-10 years.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Low tire pressure light keeps coming on although tires have been checked several times
ANSWER : The wheel sensors have a limited life of about 4 to 6 years and then the sensor battery dies. The battery in the sensor is built in to the sensor and is just like a car remote control battery. They will not give pressure signals when they die and cause the tire pressure light to come on. You will have to replace each sensor at a cost of about $60 each.

Read Full Q/A … : Tire Pressure Light coming on

My car’s tire pressure monitoring system lights come on when the tire pressure is normal
ANSWER : Your car is equipped with wheel speed sensors on each of the four wheels which monitor wheel speed while relaying this information to the ABS and traction control system (ESC) which are controlled by the car’s ECU. When the ECU senses an abnormal speed given specific conditions, it engages the ABS or traction control as needed to control the vehicle. Occasionally, these sensors can fail or only work intermittently, sending inaccurate signals to the ECU. When this happens, you may experience the symptoms you have described. The ABS or traction control system may be inadvertently activated by these false or inaccurate signals.

Your TPMS system works the same way in that there are sensors that monitor the tire pressure relaying this to the car’s computer. These sensors are known to go bad occasionally. Keep in mind this can also fluctuate easily with changes in air temperature, as this changes the density of the air which will affect the way these sensors read tire pressure. With regard to your heater turning off and on, this may be related to the blower motor relay which is what directs power to the heater blower motor. When this is faulty, this may cause the blower fan to work intermittently or sometimes not at all. I would suggest having a professional, such as one from YourMechanic, diagnose your ABS and traction control system to determine the cause of this.

Read Full Q/A … : Tire Pressure Light coming on

No dash lights, back right tail light is out, no parking lights. Brake lights work though as does head lights.
ANSWER : Hi there. In many cases, when you have electrical problems like you’re describing, it’s caused by multiple electrical component failure. It’s likely that a few electrical relays are not working; especially if you have systems that utilize the same components (such as your brake light and tail lights). I would recommend having a professional mobile mechanic come to your location to complete an electrical problems inspection first, so they can pinpoint what is damaged and recommend the right repairs.

Read Full Q/A … : Tire Pressure Light coming on

Low coolant light comes on when AC, defrost or heater is on, but only if the car is in gear and stopped, what’s wrong with my car?
ANSWER : First, you want to make sure your cooling system is full. Check the radiator not the coolant jug. And check it when it is cold. If it needs coolant, add some. Of course, I don’t feel this problem is an actual low coolant condition. I would expect to find an electrical failure in the instrument cluster or from a component or wiring harness that is connected to the instrument cluster.

As a technician, I have access to reports from technicians across the country. I could not find any reports of this problem, so diagnosing this will require an experienced tech as this is not a common problem. In addition, this happens at intermittent times making it difficult to recreate. The most challenging part of this diagnosis will be recreating the symptom. I suspect it has something to do with the brake switch circuitry because it only seems to happen when you have your foot on the brake. I would begin my diagnosis there with a wiring diagram and test light in hand. The brake switch, instrument cluster, and environmental controls all interact with each other. Something is crossed either because of a failed module or damaged wiring in a harness.

Aside from making sure the coolant is full, this will not likely leave you on the side of the road. If you take it in to be diagnosed, be prepared for them to spend more time than usual to figure it out. Since it isn’t a key problem, you may need to live with it until it completely fails making it much easier to diagnose. Either way, I do recommend having a certified mechanic diagnose the warning light to make sure there isn’t anything serious going on.

Good luck.

Read Full Q/A … : Tire Pressure Light coming on

Battery light goes on when I start car then turns off, if I rev engine light comes back until rpms go down. Abs goes comes on/off
ANSWER : Batteries can die due to faults in the charging system so ideally a suspected "faulty" battery should be load tested before a decision is made to condemn it. The only exception to this rule is if the battery is already clearly "old" (greater than 5 years) but even then once you put a new battery in, as a replacement for a "dead" battery, you have to comprehensively check out the charging system. Diagnostic Trouble Code P0460 will result in disruption of the dashboard fuel gauge’s ability to accurately report your tank’s fuel levels. The fuel gauge readings may be erratic, or read somewhere off scale. Vehicles equipped with a low fuel warning light feature may also suffer from erratic low fuel warnings in the event of a code P0460. Unless the P0460 code has been reported alongside other trouble code, all of the vehicle’s essential systems should otherwise function normally. I would recommend that you request a check engine light diagnostic to first resolve the fault causing the P0460 code to set. The check gas cap light warning light could be due a faulty gas cap and/or small leaks in the EVAP system.

Read Full Q/A … : Tire Pressure Light coming on

Pressure monitoring system comes on eventhough air pressure in tires is normal
ANSWER : There are many potential causes for this. If the light stays on continuously, the tire pressure may not be set correctly or the system may need to be reset.

Changes in ambient temperature can also affect TPMS operation, since tire pressure drops in cold weather.

If both the low tire pressure and TPMS indicators are illuminated, then the Engine Control Module (ECM), or Electrical Control Unit (ECU), has detected a problem with the system. In this case, the diagnostic trouble codes (DTCs) should be retrieved to start the diagnostic process.

Anything from a failed sensor to a problem with the control module could cause both lights to be illuminated. I suggest you get a second opinion from someone other than the dealership. YourMechanic is an excellent option to get your trouble codes diagnosed, since we make house calls.

Read Full Q/A … : Tire Pressure Light coming on

Speedometer stopped working, o/d light blinking, check engine light and low tire pressure light are on
ANSWER : All of these problems are most likely linked together by a faulty wheel speed sensor. If the ABS light is on, a fault will be stored pointing to the faulty wheel speed sensor. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the equipment to pull the fault code and repair the correct wheel speed circuit or replace your wheel speed sensor entirely.

Read Full Q/A … : Tire Pressure Light coming on

Abs light, emergency brake light, steering wheel assist light, engine light, EPC light, traction control light
ANSWER : Hello, thank you for writing in. The vehicle does utilize a lot of the same sensors for these systems. Are there any other codes that are coming up when this code appears? If so you will want to take these into consideration when processing the repair and making a diagnosis. The module may be bad, and replacing it should fix the problem. The lights should turn off once the main computer recognizes the new module and the sensors sync up. If you believe the sensors need to be cleaned you may do so. Do as minimal as possible to make sure you are not damaging the sensor or disrupting the wiring inside. A bad connection would make the lights stay on. With so many lights that are effected by the module being illuminated, the module is likely bad or does not have a connection. Check the connection first and then resort to replacing the unit. For more help with these electrical tests, contact our service department.

Read Full Q/A … : Tire Pressure Light coming on