2003 prius - no sound from 3 of the 4 speakers

The stock radio on an '03 is probably the same as on my '01. On my '01, there is both a balance (left/right) and fader (front/back) control for the sound system, available through the touch screen. It's possible to adjust both of these so that the sound only comes out of one speaker, so if you return both controls to the middle, it may start working again - try the cheap and easy stuff first.

When you get to that screen, you will see a grid of a bunch of little squares, with two green lines on the grid. If the green lines are all the way at the right side and the bottom, that's the problem. Touching the grid will move the green lines.... put them both in the center of the grid, like a +, and try again. (If you don't know how to navigate the touch screen, the user manual as a PDF should be a free download from http://techinfo.toyota.com/ .)

If both of those lines are in the middle, forming a +, and still only the right rear speaker works, then the next most likely cause is three blown speakers. One of the speakers in my rear parcel shelf quit a few years after I bought the car new. If I remember correctly, the stock rear speaker connectors are under the parcel shelf - you can see them if you open the trunk and look up, underneath the back window. (If you don't see the connectors, then they're on top of the parcel shelf - see below.) With the car turned off, unplug the connector, and use a multimeter set on "ohms" across the two pins on the speaker side of the connector. You should get something around 4 to 8 ohms. If you get infinite ohms (open circuit), then yep, the speaker is blown.

If you don't have a multimeter, either 1) scour the Harbor Freight Tools coupons/flyers until a "free multimeter" one comes around, then go there and buy a package of zip-ties or something and get the meter as your freebie or 2) get a AA battery with good charge and a couple of short pieces of wire. If the wires are insulated, strip some of the insulation off of both ends with a pocketknife. Use tape (clear office tape, masking tape, duct tape, electrical tape, whatever is handy) to tape one wire to each end of the battery, so the bare part of the wire makes contact with the end of the battery. Then, carefully poke the free ends of the wire at the pins on the speaker side of the connector. Don't hold the wires on the pins for a long time - just tap the wires on the pins. If the speaker is working, you will hear a clicking or popping noise as you poke the wires. If you hear nothing, and you're sure that the wires are making good contact with the speaker pins and the battery, then the speaker is blown.

The door speaker connectors are a little more work to get to - you need to take the inside panel of the doors off. From memory: one screw behind the silver inside door handle, one inside that plastic cup you put your fingers in to pull the door closed, and I think a plastic pin on the back edge of the door, under where the latch is. Starting by the rearview mirror, pull the plastic panel away from the metal door to disengage the plastic pegs - work your way down, along the bottom of the door, and back up by the door latch. Finally, lift the whole door panel straight up to disengage the channel at the top (with the piece of rubber that bears on the window class) from the top of the door. Unplug the cable going to the door lock and power window switch, and you can take the inside panel completely off the car. Then, you should be able to see the two-wire connector for the door speaker. Unplug it and use a multimeter or battery on the speaker side of the connector, as above.

The stock speakers are custom-made by Pioneer for Toyota; when my rear one blew, Crutchfield still sold Pioneer speakers, so I was able to get a pair of aftermarket Pioneer speakers the same size as the stock ones. They bolted in using two of the three stock bolts. I did have to move the connector from one side of the parcel shelf to the other, but there was just enough slack in the Toyota harness, and the adapters that came from Crutchfield, to make that work. To get at the bolts for the rear speakers, you need to remove that fuzzy panel that lines the rear parcel shelf. To do that, you at least have to unbolt the two child seat anchors back there (pop the plastic cover off to see the bolt). If I remember right, the rest of it is plastic pins. I think I used a pair of pliers from the trunk to squeeze some of the pins and push them up from the bottom side. You may be able to finagle the fuzzy panel out without taking the rear seat back out, but be careful of the slots for the outboard seat belts. There is a slot in the fuzzy panel that lets it come off around the seatbelt (the seatbelt stays installed), but all of that is stuffed behind the rear seat cushion and you kind of have to work by Braille. As far as I remember, the two speaker grilles and the two smaller grilles for the battery cooling intake stay attached to the fuzzy panel - you don't have to remove them.

If you want to take the rear seat back out, open one of the rear doors and push down on the back edge of the bottom seat cushion, an inch or two inboard from the outside end of the cushion. You will eventually find a loop of steel wire that comes down from the back seat cushion and is bolted to the body with a bolt with a big washer on it. Take that bolt out - careful not to lose it under the bottom cushion. Do the same thing a couple of inches inboard from the other rear door. Finally, there's a third loop with a bolt a little bit off center - if I remember right, it's a little to the driver's side of center - take that bolt out too. Then, lift the entire back seat cushion straight up (there are some hooks on the top of it that go into the parcel shelf) and take it out of the car.

Once the fuzzy panel is out, you should see the bolts for the speakers. Installation is the reverse of removal. (Now is also a good time to vacuum up all those dead bugs and stuff that were always on the back edge of the fuzzy panel, but you couldn't get to with the vacuum because the rear window glass was too close.)

I've never had to change my front speakers, so this is just from observation, the service manual, and previous car stereo adventures: the front speakers are riveted to the door sheet metal, so you need to drill out the rivets. Toyota says to use rivets to install the new speakers. Pop rivets from the hardware store are fine - make sure you get ones with a long enough grip length to suit the thickness of the speaker flange and the door sheet metal together. You may also be able to use a Tinnerman nut (one of those U-shaped things with a screw hole that clips over the edge of a piece of sheet metal) and a sheet metal screw. However, don't use one of those 3" long sheet metal screws that car stereo shops love to use - remember, the window glass has to roll down into that space behind the speaker! If you do use screws, it's probably worthwhile to temporarily plug the power window switch back in and roll down the window to see how much room you have, and select your screw accordingly.

Also, if you're fooling around in the front door, it's probably worthwhile to make sure the drain holes in the bottom are open. They let rain water, melted snow, condensation, etc that gets inside the door to get out again. Sometimes they fill up with leaves and dirt that sneak in around the glass. Look at the bottom edge of the door, near the rubber seal, and you should see some holes that go up into the bottom of the door - if I remember right, there's about 3 or 4 of them, spaced fairly evenly along the bottom of the door. Use a wood or plastic toothpick, or an unstripped piece of insulated wire, to poke around in those holes to make sure there is no crud. Sometimes applying a shop-vac hose to the hole from the outside helps.

Crutchfield doesn't currently sell PIoneer speakers in '03 Prius sizes, but they do sell some other brands. $50 or less a pair is a good target price if you have the stock radio; the amp just isn't powerful enough to justify a fancier speaker. For either the front or the back, I would look at their Kenwood, Rockford Fosgate, or JVC offerings. Sound Ordnance is their house brand and comes in nifty looking boxes with WWII airplanes on them, but the speakers themselves are junk. Someone I know did a car with them, and then had to yank them out and get a refund under the warranty when they burned out a few months later, on a stock '09 Ch*vr*l*t stereo. The nice thing about Crutchfield is that the price of any mounting and wiring adapters you need is baked into the speaker price you see on their site; you tell them what car you have and they send the right parts with your order. A local car stereo shop, or possibly even Wally World, can probably also supply suitable replacement speakers. Avoid B*st B*y, who are a bunch of lying sons-of-beeches who will be the first against the wall when the revolution comes. (I once drove a half-disassembled car out of a B*st B*y install bay, finished the stereo install myself at about half of their "surprise, we need extra parts" cost, and never went back.)

If (when) you break one of the plastic pegs while on this adventure, Toyota will be able to supply new ones at silly prices ($2-$3 each). For a better deal, take an unbroken one to the car parts store and match it up - they probably have some "generic" ones that will fit, for rather less than a dollar each. I find that NAPA stocks a better assortment of these things than their competition, at least around here - if they don't have it on the "public" shelf, they have a book with pictures and part numbers you can look at, so the counter person can get the right one from the back shelf.

I hope this helps!

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