2004 Prius, no sound from stereo

Returned from an out of town trip, the Prius started right up in the airport lot with no sign of anything wrong, but then I noticed the radio/stereo wasn't making any music. My wife and I had been listening to XM when we drove to the airport and the car hadn't been driven while I was away.

Here's what's odd--making me thing it's an amplifier fuse issue--the MFD works fine. The MFD display shows the radio stations, XM, CD, Cassette, etc. tuning in just fine like it thinks it's playing music. But no adjustment of the volume (with knob or steering wheel controls) brings any sound at all (no static, nothing).

I tried turning the stereo off and on again several times without change. I tried shutting the car down and restarting--no change.

Anyone with experience with this? Is there a separate fuse for the amp? Is it weird that it would work when I shut off the car then not work when I restart it--or is that when fuses tend to blow?

It was pretty cold out (45F) and the car was pretty cold soaked to that temp. But even when the cabin warmed up there was no change.

Would appreciate advice.

 

Thanks "dog"! But the plot thickens...
This morning when I started up (warmed garage, engine block heater, but cold outside) the problem persisted--no sound at all.

But about 3-4 minutes into driving I started hearing very sporatic, sound (the stereo was tuned to an FM channel) Thinking maybe the sound was so sporatic b/c it was an out of area FM channel, I switched to XM--same issue, but slowly, over the next 5-10 minutes the audible sound became more frequent, though "stuttery" (better when driving, worse when braking or stopped) until eventually the sound came on and stayed on like usual with the usual sound quality and no stuttering or cutting out at all!!

Could there be moisture in a connection somewhere that caused a brief short? A loose connection I should check (but why did it go from so loose there was no sound at all to tight enough to not break at all?)

Glad to have audio back, but would like to know what caused this and how to prevent it from happening at a more inconvenient time (ie. a long trip).

 

Freaking aliens, again--they're starting to piss me off!

 

The volume numbers changed easily with both the knob and the steering wheel volume controls. Just no sound came out.

 

They're baaaaccckkk!! Since my post on 10/19/11 the radio had demonstrated no issues at all. It came right on, stayed on, no stuttering or cutting out or anything.

Until this afternoon. After sitting parked at work for ~5 hours I got in the car to come home....I noticed the radio didn't come on immediately as it usually does, but before I could get out of the parking lot it came on and seemed to be fine for a few minutes. But soon it started briefly cutting out, then rapidly cutting in and out (kind of stuttering) for several minutes. By about half-way on my ~10 mile drive home it was cutting out completely for several seconds up to minutes. And by the time I got home it was completely off with rare moments of sound (see below).

Here's what's REALLY weird. When I was accelerating the sound was much more likely to cut out, even if it had been playing. And when decelerating (even just lifting my foot of the accelerator) it would 'cut in' and make sound again...the harder I would brake/faster I would slow the more likely and more sustained the sound was when it returned! By the time I got home it was basically not making any sound with the exception of a brief bit of sound when I was braking firmly to turn into my driveway.

Once home I turned the car on, I fiddled with the wires under the passenger seat going to/from the amplifier, but they all seemed snug and wiggling them didn't make the sound come on at all. I took the right vent cover off and tried to fiddle with the wires on the back of the head unit, but didn't feel up to a full dash dismantling.

So.... My sense here is that there is a wire, somewhere, that is touching something it shouldn't be and is shorting something (? the amp--b/c the head unit stays on and shows good signal), and when I slow down the wire swings free of whatever is shorting it and the sound returns. No idea why this is so intermittent though. Very frustrating.

Would really appreciate any other trouble shooting suggestions, or alien eradication methods. Otherwise I think I'm stuck taking this in to the service department to try to figure out.

 

The amp is under the seat and, as I mentioned above, I did check those wires (though I didn't pull them out) and it didn't seem to be at that end. I know how to get to the back of the head unit, but had taking the dash apart--but maybe it'll be my next rainy day project just to check. The 2nd gen Prius does not have any anti-theft device built into the head unit.

 

It was a bit colder, and both this time & the first time the car had been sitting without the EBH and it had been raining.


iPhone ?

 

Good place to start for certain. Or maybe just pull it and clean it off and reseat it to start.

 

Just an update. I did take the car in to the local Toyota Service Dept. this week, waited about 2 hours, they took the car out for about a 5 mile drive, apparently checked it top to bottom and, of course, could not reproduce the problem and therefore had no advice.

At least they didn't charge me for the "work", but suggested I bring it by if it happens while I'm out and about--yea, right.

 

Another update: when I restarted the car around noon today the stereo made no sound after working flawlessly for the past couple months. It was, again, after sitting outside in the rain in moderately cool weather (40F).

As advised at the prior dealer visit I brought it to the dealer while not working. Currently they're tracing the various wires to try to find the source of the problem. If they figure it out I'll post the results.


iPhone ?

 

3.5 hrs later they "think" it's the amplifier that has an "internal short". They have to order a replacement & repair at a different time.



iPhone ?

 

The service guy, who is also a personal friend, called this morning. He says it's $500 for the replacement (rebuilt) amp + $200 for service. That seems way excessive.

Particularly considering that the damn thing is working again this morning. I had the space heater on the car all night in the garage and, of course, the stereo was working fine this morning.

Still can't tell if this is a moisture issue, a cold issue, or a combination of the two.

Appreciate any tips on where to pick up a salvage for a package #9 JBL amp for cheap. Or if there are any decent aftermarket alternatives I'd consider those too, I'm not looking to upgrade the entire system since I'll be replacing the car in the next 6-8 months, just want a reliable audio system until then and beyond. Got a feeling this will be a DIY job.