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Test E: DTC B1681 - PATS Transceiver Module Signal Is Not Received

PINPOINT TEST E: DTC B1681 - PATS TRANSCEIVER MODULE SIGNAL IS NOT RECEIVED


E1-E2:






E2-E4:






E4-E6:






E6-E8:






E8-E10:






E10-E12:






E12-E13:






Normal Operation
The passive anti-theft system (PATS) transceiver receives voltage on circuit CDC34 (WH/OG) and ground on circuit RRT25 (VT/WH). The PATS transceiver communicates with the PATS key. During each vehicle start sequence, the PATS transceiver reads the PATS key identification code and sends the data to the instrument cluster. The instrument cluster and the PATS transceiver communicate on circuits VRT23 (VT/GY) and VRT24 (YE/OG). The instrument cluster then sends a message to the powertrain control module (PCM) to control the engine enable. The instrument cluster initiates the key interrogation sequence when the key is turned to the ON or START position.

Possible Causes
- Fuse
- Circuit CDC34 (WH/OG) open
- Circuit RRT25 (VT/WH) open
- Circuit VRT23 (VT/GY) open short to voltage
- Circuit VRT24 (YE/OG) open or short to ground
- PATS encoded ignition key
- PATS transceiver
- Instrument cluster