Skip the auto shop - Our mechanics make house calls

Q: Why is my check engine light not coming on after first turn of the key and does this mean my computer is dead

asked by on

My miata was running fine parked it for the night the next day it will not start. Turn the key on all the check lights come on except the check engine light,theirs no spark no fuel pump. It has an old battery but it still turns the motor over good just checked batt. 13.06volts . I think my computer controll is dead (ECU , ECI) im not sure what to call that black box.

My car has 182724 miles.
My car has an automatic transmission.

Hi there. It is possible that the ECU is damaged; however, it could be a simple problem like a damaged fuse, damaged electrical relay or problems with the dashboard itself. It’s best to have a professional mechanic to complete a check engine light inspection. This will allow the mechanic to attempt to access the ECU with the scanner. If it connects, then the issues are much easier to resolve. Replacing an ECU can only be done by a dealer; or authorized Mazda mechanic, which can get rather expensive.

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!
  • Home
  • Questions
  • Why is my check engine light not coming on after first turn of the key and does this mean my computer is dead

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: Drain hole issue

Mazda has two service bulletins concerning the soft top drains possibly clogging up leading to leaks that develop in the floorboard. The filter screens at the drain entrance may need to be cleaned and the drain tube itself may need...

Q: Why is the car losing power and not accelerating? 1995 BMW 318is

Hello and thank you for contacting YourMechanic. Check the ground wire from the main engine to frame ground to the right side engine mount. If this wire is corroded or loose, this will cause the engine to loose power on...

Q: The manual and how to fix it....5th gear is not working I went by a machanic n the gears are still not going in well

Hello. If you still are not getting 5th gear then you have an issue within the transmission. If the transmission is brand new then it should be taken back to where you purchased it from. If this was a used...

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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
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.