Question

2002 Dodge Neon 2.0L with engine code P1684, it backfires then runs rough and loses power.

Answer 1

H there,

This code is not the cause of this. I would check the ignition coil and spark plug wires as possible culprits.

P1684 - BATTERY WAS DISCONNECTED

WHEN MONITORED 
Whenever the key is in the Run/Start position. 

SET CONDITION 
This code is set whenever Transmission Control Module (TCM) is disconnected from battery power B+ or ground. It will also be set during the DRBIII Quick Battery Disconnect procedure.

POSSIBLE CAUSES 

• QUICK LEARN WAS PERFORMED
• RECENT BATTERY DISCONNECTION
• TCM WAS REPLACED OR DISCONNECTED
• INTERMITTENT WIRING AND CONNECTORS
• FUSED B+ CIRCUIT TO TCM OPEN
• GROUND CIRCUIT OPEN

Answer 2

P1684 DODGE Code - Battery Power To Module Disconnected
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