2006 Civic Immobilizer Indicator Is Blinking, Engine Won’t Start

The engine does not start, and the immobilizer indicator is blinking (especially if the battery recently went dead and the engine was jump-started).
PROBABLE CAUSE
The immobilizer IMOES code has been erased.
NOTE: This problem occurs only if all these conditions are met: • The security system is set. • The battery goes dead. • Battery power is connected to the vehicle, then disconnected in a very short period of time (milliseconds).
If the vehicle meets these conditions, or if the condition is unknown, go to DIAGNOSIS.
DIAGNOSIS
NOTE: When the immobilizer system is not allowing the engine to start, the results vary depending on the model and how quickly the ignition key is turned. 2006 Civic 2-Door, 4-Door, Si, and GX • If you quickly turn the ignition switch from LOCK (0) to START (III), the engine starts and runs for about 1 second, then shuts off. • If you turn the ignition switch to ON (II), then pause before turning to START (III), the starter cranks, but the engine does not start. • When the ignition switch is returned to LOCK (0), the indicator blinks 10 times. 2006 Civic Hybrid • During moderate weather conditions, if you turn the ignition switch to START (III), the gauges and gauge indicators come on, but the engine does not crank. • During extremely cold conditions (about 0° F or lower) or a low IMA battery.

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