Normal Operation

The Passive Anti-Theft System (PATS) transceiver receives voltage from the Smart Junction Box (SJB) on circuit CBP36 (BU/BN) and is grounded on circuit GD112 (BK/GN). The PATS transceiver and the Instrument Cluster (IC) communicate on the TX and RX circuits VRT24 (YE/OG) and VRT23 (VT/GY). 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