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Test D: DTC B1602 - PATS Received Invalid Format Of Key-Code From Ignition Key Transponder

PINPOINT TEST D: DTC B1602 - PATS RECEIVED INVALID FORMAT OF KEY-CODE FROM IGNITION KEY TRANSPONDER


D1-D2:






D3-D4:






Normal Operation
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 will then send 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.

DTC B1602 - sets when only a partial PATS key was read. Remote starter equipment can also cause this diagnostic trouble code (DTC).

Possible Causes
- PATS key
- PATS transceiver
- Instrument cluster