Normal Operation

The Passive Anti-Theft System (PATS) transceiver receives voltage from the Smart Junction Box (SJB) on fuse 36 (5A). The PATS  transceiver and the Instrument Cluster (IC) communicate on the TX and RX circuits. The IC  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 (PATS  Transceiver Module Signal Is Not Received) - sets when the PATS transceiver signal is not received by the IC  . This DTC can be caused by circuits between the PATS  transceiver and the IC  , or circuits to the PATS  transceiver. This can also be caused by using the incorrect PATS  transceiver part number.

This pinpoint test is intended to diagnose the following: 

• Fuse
• Wiring, terminals or connectors
• PATS  transceiver
• IC