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Home >> Saturn >> 2004 >> ION L4-2.0L SC VIN P >> Repair and Diagnosis >> Relays and Modules >> Relays and Modules - Powertrain Management >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Description and Operation >> Theft Deterrent System Function
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Theft Deterrent System Function

ENGINE CONTROL MODULE

The engine control module (ECM) contains the remainder of the logic of the theft deterrent system. If a class 2 message containing a valid password is received from the BCM, the ECM will allow starter engagement. If the ECM does not receive a class 2 message, or receives a class 2 message with an incorrect password, the engine will not crank.
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