DTC 44: Last Transmitter Message Received Had Encryption Error: Description
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The digital RF message received was from a Remote Keyless Entry (RKE) system transmitter that is programmed to Body Control Module (BCM), but message did not pass encryption security test. No remote function capabilities will exist.
DTC 44 will set when RKE system transmitter has been in program or re-synchronize mode while out of range of BCM. Fault may also be present if digital RF message has an error due to outside noise from surrounding environment, or if transmitter is defective.
Most likely cause is that RKE system transmitter is out of synchronization. To re-synchronize transmitter, press LOCK and UNLOCK buttons on transmitter simultaneously for 5 seconds.