How to Test if Your ECU Is Bad?
By JEREMY PROOME on Jul 14, 2025To test whether your ECU is faulty, a comprehensive diagnostic test needs to be run on your vehicle’s Electronic Control Unit. However, vehicles will produce common symptoms that can suggest your ECU is bad prior to a full test.
Some of the key symptoms of a bad ECU are:
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Poor engine performance
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Not starting
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Poor fuel economy
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Check-engine light
How to Test Your ECU Status
While these are commonly associated with ECU problems in a vehicle, there are a wide array of reasons as to why the ECU could have failed, or perhaps a complementary component, such as the car’s sensors. So, everything from mechanical damage to an electronic fault could trigger the ECU to fail.
Therefore, to fully test the ECU, you should contact a professional vehicle diagnostic team, who can use an OBD (On-Board Diagnostics) scanner to get an accurate error code and indication of what the problem may be.
Mail in automotive electronic repair services
The ECU Pro offers an affordable mail-in repair service for automotive electronics. To have your unit repaired, simply remove the part and mail it to us. Our professional team will either test, repair, or clone your unit.
Our team has over 30 years experience in automotive electronic repairs. We specialize in German vehicles such as BMW, Mercedes and Mini. Our main focus is engine control unit repairs ( ECU, PCM or DME). Our state of the art facility has over 30 test vehicles to ensure that all parts are tested in actual vehicles before being returned to our clients.
Most of the services we provide is plug and play and doesn't require any additional coding.
