Answer
Oct 02, 2025 - 09:37 PM
On the BMW i3/i3s, if your car didn’t come with the Harman Kardon audio upgrade, then the wiring isn’t fully pre-run for the extra speakers.
- Center speaker: the base audio cars don’t have the harness for the dash center channel. You’d need to add wiring yourself if you wanted to retrofit it.
- Rear door speakers: same story — some base cars only have the front stage wired up. The wiring for rear doors usually isn’t there unless the car was optioned with them.
BMW tends to keep the looms as simple as possible to save cost, so they don’t prewire unused speaker runs. So if you’re planning a retrofit, expect to run new wires or buy a retrofit harness.
