Re: Stereo keeps changing volume randomly autonomously?

Yousuf Khan <[email protected]> wrote:

> So the stereo system in my 2008 Tribeca has started to get a mind of
> its own. For some reason, the volume goes up or down on its own,
> without you touching the controls. You can see the volume level
> changing on its digital display, it'll hunt around from 0 to 30 or
> anywhere in between, except where you last left it. When this
> happens, you can still manually adjust the volume with either the
> volume knob on the console or on the remote volume control on the
> steering wheel, but it won't stay there for long. Problem started a
> couple of days ago, and it seems to start happening maybe after 5
> minutes after starting the car. What could possibly be causing this
> problem?
> 
> On a possibly related note, the car's battery has had some corrosion on 
> it, possibly some cells have gone bad. Could this have anything to do 
> with it? Just throwing that out there as a random observation, I'm not 
> saying that this is the cause, just asking.

The faceplate is removable.  

https://www.youtube.com/watch?v=MRyHv5dI9QE

You could remove it, remove each cable plug one at a time, and reset
each connector to see if the problem is a loose plug.  Also bend the
cable at the connector when plugged in to check if a wire might have a
poor or intermittent connection.  Don't remove the whole unit.  Just
remove the faceplate and wipe its connector blades by cycling its
contacts (unplugging and plugging in several times).

Another suggestion was to unplug the steering column connector that
connects the steering wheel radio buttons, including volume, and then
just test the radio's own volume controls.  Could be a flaky button on
the steering wheel.  Maybe the steering wheel button is broken, so it
bounces on its contacts while driving.

From what I read (quickly), could be the radio went bad.  Others noted
the erratic volume level, and then eventual death (no volume).  You may
have to replace it.

Corrosion on the battery [terminals] is due to outgassing.  Sounds like
the battery needs replacing.  The alternator will try to charge the
battery when low, but it cannot compensate for a defective battery that
won't charge evenly causing the voltage to fluctuate.  Even if the shop
or store does a load test on the battery, and it passes, remove the
terminals, clean them, and make sure they are tight.  Then coat with
silicone grease or the battery spray to keep them from corroding again.

Although the battery might be maintenance free, it may have lids (vent
caps) on the cell holes.  If you ever put any distilled water in those
holes because the electrolyte looked low, you might've overfilled the
cell(s).  Overfilled cells will overflow when the electrolyte expands.
Some batteries have vent caps with manifolds where the outgassed
electrolyte will condensate and drain back into the battery.  Most are
just cheap caps.  As batteries age, the voltage drops (sulfation,
reduction of acid), and require longer [re]charging which has the
battery get warmer for longer with more outgassing.  Never add distilled
water before charging the battery, only after charging it to make sure
you know what is the running or operational level of the electrolyte.
Although the outgas is hydrogen, it can bring along some of the
electrolyte (acid).

Do you use a trickly charger or battery maintainer?  Got a hygrometer to
measure the acidity of the electrolyte in each cell?