What does it mean?
B1485 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Channel 8 Audio Speaker Output Circuit High .
Symptoms
- No sound from the channel 8 speaker, or a steady hum, buzz or thump from that position
- The amplifier keeps the channel disabled until the fault is repaired
- The fuse on the circuit feeding the speaker line may blow when the contact is solid
- The fault usually starts right after audio, trim or seat work
- Code is set again every time the system powers up
Likely causes
- Speaker wire chafed against a live circuit routed in the same loom
- Power wire joined to a speaker lead during an aftermarket audio or accessory installation
- One of the two output leads open, so the line floats at a high level
- Corroded terminal or a poor splice raising the measured voltage
- Water bridging a speaker pin to a live pin inside a shared connector
- Amplifier output stage failed and holding channel 8 high
How to fix it
- Use fader and balance to identify the physical speaker for the channel
- Disconnect the amplifier connector and the speaker, then check both output wires for voltage with the ignition on; there should be none at all
- Note whether the voltage is permanent or ignition-switched, which narrows down the feeding circuit
- Remove trim along the route and look for melted insulation, chafe against a live wire and non-factory splices
- Check both wires for continuity end to end so an open leg is not mistaken for a short to power
- Remove aftermarket taps, repair the damaged section and re-route it clear of powered wiring
- Test the output with a known-good speaker before condemning the amplifier
- Clear the code, cycle the ignition and verify normal output from that position