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 January 30, 2017

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.

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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.

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