Normal Operation

The passive anti-theft system (PATS) transceiver receives voltage from the smart junction box (SJB) powertrain control module (PCM) power diode on circuit (L/G) and is grounded on circuit (B/W). The PATS transceiver and the instrument cluster communicate on circuits (B/GY) and (V/BR). The instrument cluster compares the key code stored in memory and sends a message to the PCM to enable the starter and fuel injectors if the key code is correct. DTC B1681 - sets when the PATS transceiver signal is not received by the instrument cluster.

This diagnostic trouble code (DTC) can be caused by circuits between the PATS transceiver and the instrument cluster, or circuits to the PATS transceiver. This can also be caused by using the incorrect PATS transceiver part number.