Have been having problems with the radio in 2003 Sienna with it losing all station presets upon starting. If I turn the key to the "on" position the radio comes on and is fine. However, when I start the engine the radio shuts off and when turned back on all the presets are lost. Dealer wants to change out the radio though the reasons why didn't sound very convincing. Seemed more like they couldn't determine what the problem was and was just going to start replacing stuff until they found it. Any ideas?

My 98 Camry does the exact same thing. Used to be it was every once in a while, now it is every time I start the vehicle. I thought maybe it was battery or alternator related, so I put a charger on the battery and topped it off - no dice. So either the radio unit has some power source (button battery or something?) that is toast, or there is a short someplace. Rather frustrating as I hate to replace the radio unit only to have the new one do the same thing because that wasn't the problem.

Dave

Just as a followup to this question, I took the Camry to an independent audio dealer, who ran voltage and other electrical tests on the car. He found that my problem is internal to the radio. So Rogerwh, especially if your Sienna is still under warranty, you might just let them replace the radio. Otherwise you might get a second opinion. I'm looking at possibly replacing mine with a Sony aftermarket unit that can handle our MP3 players.

Dave

Thanks WingerDave. I'm guessing the issue is internal to the radio as well. The clock, which is separate from the radio maintains the correct time. If I disconnect the battery even for a few short seconds the clock typically needs to be reset so I'm now guessing if it was an ignition short the clock would likely require resetting as well.

Unfortunately I'm not under warranty due to mileage so I didn't want the dealer to just go about replacing stuff.

I may go the same route you did and get an audio shop to check it out.