Q: Changed the trans/motor mount and now car will not crank/start. I get dash lights, headlights, etc but now the immobilizer is on

asked by on January 22, 2018

Changed trans/motor mount under the battery box and now the car wont crank/start. I get all my interior lights, radio, power locks/windows etc. All function. But when i turn the key i only get silence. Battery fully charged and brand new. The car symbol with a key through it is flashing rapidly and the car acts like it doesnt recognize my key. And the obdII port says theres no communication with the ecu.

My car has 240000 miles.
My car has an automatic transmission.

Hi Jaime. Thanks for contacting us today. The only thing that comes to mind is that you’ve experienced some sort of electrical short or overload recently. If you replaced engine mounts without disconnecting the battery or the battery arched somehow, then it’s likely that the ECU has a rather significant error or has activated a security protocol to disable the ignition system. This is likely why you’re OBD-II scanner is not linking to the ECU. Unfortunately, this is something that needs to be verified and resolved by a factory dealer or Mazda specialist, who has access to the security system software.

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