The rear main speakers in my '93 SC400 w/ Nakamichi have stopped working. The subwoofer and front speakers continue to work fine. I'd like to know where to look for the problem first - head unit? amplifier? wires/connectors?

 

remove the speaker grills from the rear deck and lightly apply even pressure to the cone moving it up and down to see if it scrapes on the way down. if it does the speakers are shot. another way is to use a volt meter and see if you have an ohm load on the speaker with the wires disconnected.

 

I am having problems with my radio in my 99 SC400. First problem was when I was cleaning my car and playing my radio (engine not running), the radio stopped working and the display was going in and out. I turned the car off and back on and the radio worked fine. The second problem was when I was at a traffic light with the volume up, I got a lot of static, not like losing radio signal, but almost like a bad speaker. As soon as I would hit the gas, the radio played fine. Next stop light, same thing. Any ideas? I would just replace the entire system, but it's under warranty and the dealer insist on trying to fix it. Radio has been completely checked out and is working fine. Could it be a bad Amplifier?

 

horton & SteveTPA, Had similar problem with my system and turned out it was blown speakers. The link below (Post#93) shows steps that need to be taken to replace the rear speakers if blown.
https://www.clublexus.com/forums/sho...=109384&page=7

I performed a test on my rear speakers, by hooking up a small ohm working speaker to the (+/-) connections in the trunk of the car. I bought a small cheap speaker at Wal-mart. Inorder to do this you have to take down the rear right side (where the CD unit is located) corner lining panel. After doing this, I would take a look at the drainage (sunroof , gas over flow) tubes to see if they're connected properly and amplifier (under the cd unit) for water or rust stains on the amp. Water or rust could mean a short in the amp. Next take down the lining acting like the back wall of the trunk. This will give you access to the speaker (+/-) disconnect existing wires and attach the working speaker if you get sound you have blown speakers.

 

Would a blown speaker cause the radio display to flash on and off? The dealer is still trying to figure this out. I just want my car back at this point.

 

Picked up my car today from the dealer. I have to go back on Monday to try to figure this out. The noise it makes when I am at a stop light with the volume cranked is embarrasing. At least I can get away from the light quickly. LOL

 

Dealer found the problem. The battery. Not sure how a weak battery only affects the radio, but there you have it.