Audio Systems: 1991 GMC Stereo amplifier hidden turn on, stereo amplifier, bad advice

Question
I used to be able to remember how to turn the hidden amplifier on in my pickup. I think it has something to do with pushing the fade and the balance at the same time. Do you know if this is correct?

Answer
Sorry, but specific questions about particular models of cars and/or audio systems for them is impossible for any "expert" to answer, as I don't own the car nor the audio equipment.  Research on the Web using search engines or call your auto dealer for assistance.  Wouldn't want to fry something serious in your car/truck with bad advice, like the computer!  Cheers, Wink