What does it mean?
B1586 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Chime Open Or Short High .
Symptoms
- Dash illumination drops to its lowest level or goes out completely and cannot be raised
- Brightness is stuck at minimum whatever the control is set to
- Instrument lighting flickers with vibration over rough surfaces
- Switch and radio backlighting go dark while the headlamps still work
- On the chime variant, the warning chimes are silent or sound continuously
Likely causes
- Decrease input wire chafed against metal behind the dash, holding the circuit at ground
- Dimmer control stuck or shorted internally, keeping the decrease request active
- Soft drink or cleaning fluid contamination inside the control, bridging the signal to ground
- Bent connector terminal touching the ground pin
- Harness damage from a radio, dash camera or other accessory installation
- Module input pulled low internally
- On applications where this code refers to the warning chime, an open or a short to voltage in the chime driver circuit
How to fix it
- Unplug the dimmer control and see whether the code stops setting, which separates the control from the wiring
- With the control unplugged, ohm the decrease wire to ground; a near-zero reading confirms the short is in the harness
- Inspect the loom behind the dash and along the column for insulation worn through to metal
- Check the control for liquid contamination and for a contact permanently closed to ground
- Repair the wire and secure it clear of metal edges instead of just taping it
- Replace the dimmer control if it measures low to ground with the connector removed
- On the chime variant, check the chime driver output and the speaker circuit for an open and for a short to voltage