Symptoms: No consistent sound from CD, AM/FM, Nav. Popping sound on all speakers occurring about every 10 seconds. Sound will cut out and all that is heard is a popping sound like electronics resetting. When sound is present, it sounds fine. Duration between operation and non-operation varies.
On occasion the unit will operate on its own with no response to any button pushes on the unit or the steering wheel. The radio will play but the buttons will perform their appropriate function.
For example: FM station is playing through the speakers but the CD player will change tracks, scan, and switch disc. Pressing the power button or changing volume has no effect. It acts as if the input is coming from a hidden unit.
Nav audio is not heard during the outages.
This occurs regardless of headlight operation, nav operation, dimmer settings, car in motion/parked, ECU running, engine off/idle/under load.
Trouble shooting: I measured the voltage at fuse #10 with the engine off and measured +12.40V. Voltage did not fluctuate with popping/operation. Pulled the fuses for Audio(#10), Amp(#11), Nav monitor(#12) and Phone(#13). Fuse 10 & 11 killed the sound altogether as it should since it is the unit and the amplifier. Pulling 12 and 13 has no effect on operation/sound issue.
Assumption: With the radio operating on its own and not accepting user inputs, I assume that one of the following is hung up or failing.
- Audio Module
- Accessory Electronics Module
- Steering Wheel Module
Is there a safe method to resetting those modules without visiting a garage?
Any suggestions are welcome. Two other sites list similar symptoms but didn’t post the fix action.
Car Details: 2006 V70R MT, 72,000 Mile, no current fault indications, 70F outside temp at first indication.