I have a '91 300 CE. The radio speakers come and go on the drivers side. I can switch the speakers to the front and turn the radio volumne and it works. When I move the switch from the back to the front it makes a hizzing noise. What do I need to do to fix it?
Thanks, jmerc6

You may have a bad tuner box in the trunk area or the amplifier may be bad. Check those items and let me know.

Cleeve Morrison
La Jolla Audio Repair
www.lajollaaudiorepair.com

Thanks for the guidance. Now, how do I check them? With an Ohom meter?

Check to make sure the cables are connected. Then check the fuse in the back of the tuner box (7.5 amp). If that is good then check with a voltmeter to see if you have voltage to the 4 pin power plug on the tuner box. The RED wire should have 12 volts all the time. The BLACK wire should have 12 volts when the car is on. Let me know what you find.

Cleeve Morrison
La Jolla Audio Repair
www.lajollaaudiorepair.com

Thanks for the guidance. Right now I'm in the middle of pulling the cylindar head. As soon as I get that done. I'm going to start on the radio.