B1680
Alarm Panic Input Circuit Short To Ground
Body Chassis/Safety Panic alarm circuit 🟢 Low — Fix at next service
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What This Actually Means
In plain language — no jargon

The panic alarm button circuit is shorted to ground, meaning the electrical wire is touching metal and creating an unwanted path for current. This is like a light switch that's stuck in the 'on' position because the wiring is damaged.

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Symptoms You May Notice
3 known symptoms for this code
Panic alarm button does not function or activates unexpectedly
Security system malfunction or warning lights on dashboard
Possible battery drain if circuit remains shorted
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors the panic alarm input voltage to detect normal button press signals, which should show a voltage change when activated. A short to ground keeps the voltage constantly low (near 0V), which the ECU interprets as a continuous fault condition rather than a discrete button press.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Panic Button Input Voltage 5V (idle) → 0V (pressed) Constant 0V or below 0.5V at rest
Circuit Resistance 10kΩ+ (open) to <1kΩ (pressed) <100Ω (shorted to ground)
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Panic button wiring harness
Inspect the wiring from the panic button to the security module for cuts, abrasions, or bare wires touching the chassis and repair or re-route as needed.
2
Panic button connector
Disconnect and reconnect the panic button electrical connector to reseat it and remove corrosion causing the short.
3
Panic alarm button assembly
Replace the panic button unit if internal components are damaged or if the wiring cannot be repaired.