Skip the auto shop - Our mechanics make house calls

Q: Check Engine light comes on and goes off

asked by on

The light in the speedometer red needle is not working. Also, the Check Engine light comes on and goes off.

A: If the speedometer is not working but the r...

If the speedometer is not working but the rest of the instrument cluster is, the issue is probably the vehicle speed sensor. This sensor is the main input to the control module for speedometer control. The problem could also be with the wiring or the speedometer itself. There are hundreds of reasons the Check Engine Light might be on. The powertrain control module (PCM) takes inputs from dozens of sensors. It then uses this information to control outputs such as fuel delivery and emissions equipment. If the PCM detects a problem anywhere in the system it will illuminate the Check Engine Light. A failed vehicle speed sensor could cause both of the problems you are having. A trained professional, such as one from YourMechanic, will be able to inspect your vehicle’s speedometer issue and Check Engine Light to give you a definitive answer for what repairs are needed.

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: Car cranking, but not turning over

Hello, there are many possible reasons for a no-start. Your description is a little confusing since you say it crank but it doesn't turn over. In auto terminology, "crank" and "turn over" have the same meaning. If what you are...

Q: brake pedal goes all the way down

I am assuming that once the brake pedal engages the brakes, that the car stops ok. One thing in particular comes to mind and that is seized or binding caliper slides. One piston calipers have to be mounted on slides....

Q: Engine Quit in August of 2016, Replaced, Light Still On

There are a whole myriad of reasons for the check engine light to be on. It would really be necessary to find out why the check engine light is on. Pulling the codes will at the least tell where to...

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...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.