How do I fix OBD fault code B1340?

Inspect the chime input circuit wiring for damage, pinched wires, or corrosion and repair or reseat connectors.. Test with a multimeter; if shorted internally, replace the chime unit.. Check the fuse dedicated to the chime circuit and replace if blown or burnt.

OBD Code B1340: Chime Input Request Circuit Short To Ground

Q: What does OBD code B1340 mean?

Chime Input Request Circuit Short To Ground. The chime/bell system in your vehicle has an electrical short to ground, like a wire touching the car's metal frame. This prevents the chime circuit from working properly and triggers a warning light.

Q: What are the symptoms of fault code B1340?

Chime or bell does not sound for warnings or alerts, Check Engine or warning light illuminated on dashboard, No audible feedback for door ajar, seatbelt, or key-in-ignition warnings

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What This Actually Means

In plain language — no jargon

The chime/bell system in your vehicle has an electrical short to ground, like a wire touching the car's metal frame. This prevents the chime circuit from working properly and triggers a warning light.

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Symptoms You May Notice

3 known symptoms for this code

Chime or bell does not sound for warnings or alerts

Check Engine or warning light illuminated on dashboard

No audible feedback for door ajar, seatbelt, or key-in-ignition warnings

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Embedded Systems Insight

What the ECU/ECM is actually computing

The body control module (BCM) monitors the chime input circuit voltage to detect requests from various vehicle systems. It expects a high voltage signal when the chime should activate and detects when the circuit is shorted to ground (0V), indicating a wiring fault or component failure.

Voltage & Parameter Thresholds

Parameter	Normal Range	Fault Condition
Chime Circuit Voltage	5-12V when inactive, transitions to ground or high on request	Continuous short to ground (0V) or resistance below threshold
Circuit Resistance	>10kΩ at rest	<1kΩ indicating short to ground

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Diagnostic & DIY Fix Guide

Check these in order — from cheapest to most complex

1

Wiring harness and connectors

Inspect the chime input circuit wiring for damage, pinched wires, or corrosion and repair or reseat connectors.

2

Chime speaker/buzzer module

Test with a multimeter; if shorted internally, replace the chime unit.

3

Body Control Module (BCM) relay or fuse

Check the fuse dedicated to the chime circuit and replace if blown or burnt.