Skip the auto shop - Our mechanics make house calls

Q: My car's tire pressure monitoring system lights come on when the tire pressure is normal

asked by on

On occasion, my esc light has gone on in the last few years, but would soon go off. All of a sudden I have all sorts of issues.

Recently, the tpms showed pressure issues with the front driver's side tire. My husband checked and added a little air, even though his gauge didn't show a need. That light went off, and now it is showing 2 other tires are low.

In addition, my heater keeps turning on by itself even after I turn it off. Any help with resolving these issues would be great!

My car has 101000 miles.
My car has an automatic transmission.

A: Your car is equipped with wheel speed senso...

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Slight resistance when driving forward, ABS light is on.

I would have a mechanic check it out to determine why your ABS light is on. They can check ABS codes with a scan tool to determine the problem. It may be a bad wheel speed sensor.

Q: How does the tire pressure monitoring system work?

Your car is equipped with a tire pressure monitoring system (TPMS) that checks the pressure in each tire via a special sensor mounted inside the tire (it’s connected to the valve stem). When the system detects a drop in tire...

Q: Car overheating due to radiator crack

When your engine is idling, the vehicle is likely stopped which lowers the airflow through the radiator. The more airflow the radiator receives the more likely the engine is to remain cool. When the air conditioning is turned on the...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...