I have a 2001 V70 T5 with the AM / FM, CD, Cassette player. I had replaced the driver's door mirror assembly at least 2 times prior to this with the speakers continuing to work fine once the door is reassembled. However, about 5-6 years ago, I noticed the drivers door loud speaker / tweeter combination would cease to function. I managed to regain function by increasing the base to all the speakers momentarily by using the switch on the front of the HU 613 stereo unit, then turning the base down again. But sooner or later the speakers would cut out again. Lately the center speaker that resides on the dash and the front drivers door speakers have ceased to function. All other speakers (extreme rear corners both left and right, rear seat speakers (left and right doors) function just fine.

What I have currently done:

- tested the driver's door speakers by hooking them up to a separate stand alone stereo while they are disconnected from the car stereo system - they both work - I have NOT tested the center mounted dash board speaker this way however.

- tested the continuity of the driver's door speaker wires while attached to the car wiring system (but NOT connected to the back of the car stereo unit) and the continuity on the wires appears OK. I did not test the center dash mounted speaker for continuity however.

- Accessed the equalizer by turning on the car stereo while continually pressing the Source knob down, then continuing to hold the Source button down until the various functions appear. I tested the system with the functions loaded to the limit ( # 6) and then again down to the lowest (#1). Again the driver's door speakers and the center dash mounted speaker failed to work.

- All connectors and male connector pins on the stereo unit appear to be clean without corrosion.

I have the VIDA software on my laptop and it suggested looking at the connectors VERY CAREFULLY even with a magnifying glass. I have yet to do this.


Vida explains that I need to attach a "breakout box" and check for a faulty ground. However, I do not have such a fixture nor do I have the equipment to check for any faults in the stereo system.

What am I missing here guys? Do I need a new in dash stereo unit?

I live in the Milwaukee, WI metropolitan area and have been looking for a repair shop that could fix this but to no avail.

Any suggestions are most appreciated.

Thanks in advance!!

SKIP

PS Removing the Stereo prevents you from safely driving the vehicle as the SRS airbag system spits a code that takes $100 + to reset.

Back in the good old days with my 1998, the passenger front speaker did the same thing. I eventually found a speaker at a P&P and replaced it. The fabric cone developed a very small crack, so the sound would come on if I turned up the volume and continue for a while with the volume decreased, eventually turning silent again.

The tweeter speakers on the dash came unglued - the magnet fell off! Stupid green glue! All I did there was glue the magnet back on.
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Keeping it running is better than buying new

I'd be suspicious that vibration has caused a micro crack in the solder connection where the speaker wires connect to the speaker.

I'm not in possession of the wiring diagram for this car. Are you? Why would a poor ground path have any bearing? I wasn't aware that the stereo used the body of the car as a conductor to the speaker. You should have 2 wires going to each speaker. While running the stereo, flex each speaker connector tab to see if there is a bad connection there.
When you turned up the bass, it could have jarred the speaker enough mechanically to restore the connection, a sign of a continuity problem at the speaker.

If that fails, can you try substituting a speaker with the same impedance -- see if it works OK. That would pinpoint the problem to the door speaker.