Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Phase Test
Do this test to confirm proper speaker phasing.
1. Insert the audio Diagnostic CD (07AAZ-SDBA100) into the audio unit or the audio-navigation unit.
2. Play track No. 2 (phase) at a normal, or slightly higher than normal, volume level.
3. The voice should sound centered and focused when it indicates it is in-phase.
4. The voice should sound diffused, and have less bass when it indicates it is out of phase.
- If the voice changes from in-phase to out of phase as indicated by the prompt, the phasing is correct. Go to Electrical Noise Test.
- If the voice always sounds out of phase, phasing is not correct. Check for:
- Shorted speaker wire
- Open in speaker wire
- Shorted speaker
- Loose connection or poor pin fit
- Faulty audio unit or audio-navigation unit
- Faulty stereo amplifier
- Aftermarket audio components like amplifiers, speakers, etc.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.