Q: car won't start security light flashing

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I changed the engine on my car using back the original wire harness and ecu now it won't crank and security key light keeps flashing is there a way I could reset it please help my name is mike and I am from Guyana south America
My car has an automatic transmission.

Hello Mike, thank you for writing in. The vehicle may be activating its immobilizer system which was demanded to be installed by insurance companies. If you have access to an OBD-II scanner, you will want to scan the vehicle for security codes. These may help you figure out what about the system has engaged it and what you need to do to reset it. Without that information, you may find this to be very difficult. In addition, tuners and manufacturers have the technology needed to access the computer, and find the information needed to reprogram, flash, or reset the security system. It may also be something as simple as a poor electrical connection. Using the stock parts from the original engine, the new engine should theoretically start right up. If you replaced sensors for the new engine, they may also need to be programmed into the new computer system. You should scan the vehicle, and take further diagnosis from there. For more help, contact our service department.

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