Skip the auto shop - Our mechanics make house calls

Q: ECU disconnected

asked by on

I lost my original car key i tried to get another one programed and it said ECU disconnected
My car has an automatic transmission.

Hi and thanks for contacting YourMechanic. First, remove the ground cable from the battery and let it stay off for 12 minutes. Then hook up the battery cable and retry the key. If your vehicle still gives you the same message, then the programming in the key does not match the ECU to the vehicle. Try putting the key in the drive door and lock and unlock the door 3 times. Then retry the key. This usually makes the car ECU recognize the key for starting. If you need further assistance with your vehicle, then seek out a professional to help you with your replacement key.

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

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: Hello Joshua. My check engine light came on and I took my 2009 Toyota Rav4 to my mechanic. after running diagnostics he came back

Hi William. The canister purge solenoid, more commonly known as the purge valve, helps facilitate the flow of fuel vapor from the charcoal canister to the engine for burning during the combustion process. The purge valve remains closed when the...

Q: I am making a appointment for today

Hi Rachael. Anytime you have a service light illuminate, it's best to first have a professional mobile mechanic complete a check engine light inspection. When there is an electrical or mechanical fault that is causing the light to illuminate on...

Q: How do I remotely start my car?

The remote start system allows you to turn on your car without being in the vehicle. If your vehicle is equipped with the remote start system, then you access it through the remote keyless entry (RKE) transmitter. To turn on...

Related articles

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...
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...