Sorry if this thread irritates the experts. I am in no way on of you! I have a Panasonic in-dash CD mount. One day it just stopped making sound. The tuner still shows a signal coming from the radio--CD does the same thing---just no sound. I have noticed that when I start the truck I get a split second of static from the back speaker--otherwise, no sound. I have been told that it could mean the amp has gone out on the system, but of course, when I take it to a shop they just want to sell me a new one. This may be what's necessary, but I hate to do it without asking around first.
Here is how I diagnose a radio problem. ( No Audio) With a Digital Volt Meter ( DVM) select volts, 20-volt range. Black lead to a good chassis ground, probe all the speaker leads. You should see a voltage on all of them. The voltage should be approximately 1/2 of battery voltage. But Most Importantly They Must Be The Same!!!! (within 1/10th of a volt) If one of the speakers reads 0 volts that speaker is bad, disconnect that speaker and see if the others now work. (it should) If the voltages vary widely, the output in the radio is bad. Replace the radio or replace the output. If its an expensive radio, fix it, if not replace it. Example, my basic labor rate on an output replacement is 88.50 + the price of the output. Outputs typically run around $15.00 to $20.00. Now if you dont have access to a DVM. DISCONNECT ALL the speakers at the bacK of the radio. With a test speaker (any good speaker you have laying around) Check to see if you have sound on each speaker lead coming from the radio individually. You CANNOT use a speaker mounted in the car, you don't know if its bad and causing the problem. All modern radios will shut down ALL AUDIO if the is a shorted speaker or if a speaker wire is shorted to ground or shorted together. Hope this helps.
