Normal Operation

Remote locking and unlocking of the doors is accomplished by the Smart Junction Box (SJB) receiving a command message from the Remote Keyless Entry (RKE) Integrated Keyhead Transmitter (IKT). The SJB energizes the appropriate relays to lock or unlock the doors. The RKE transmitters and SJB also utilize a rolling code to prevent the code from being "captured" by a code grabber. The system advances the counter in the RKE transmitter and SJB every time an RKE transmitter button is pressed.

• DTC B1139 (Invalid Transmitter Identification Code) - a continuous DTC that sets when the Instrument Cluster (IC) or SJB detects an invalid Transmitter Identification Code (TIC) from an IKT.
• DTC B2425 (Remote Keyless Entry Out of Synchronization) - a continuous DTC that sets when the SJB detects the rolling counter received from an RKE transmitter is 1,024 times greater than the rolling counter stored in the module.

This pinpoint test is intended to diagnose the following:

• IKT
• IKT battery
• IKT button pressed a substantial amount of times while outside the range of the vehicle
• IKT programming
• SJB