I ordered the service manuals and they will be here next week. In the mean time can someone tell me the color of the wire coming out of the radio that turns on the monsoon amplifier mounted on the back deck? Also, what voltage should I see on this wire when the radio is turned on? Thanks for any assistance. The car is a 2004 Grand Prix with monsoon (including the middle speaker up front) and XM features.
Also, using an earphone I tapped into the pre-amp level signal between the radio and amp and I can hear both the radio station and chime through the earphone. Problem is I’m getting no sound (music or chime) from any of the speakers. I’ve already replaced the monsoon amp in the back deck. I’m speculating that the radio is not sending the signal to the amp telling the amp to turn on. Any thoughts would be welcome.
Later...I got help from a local pro. The wire from the radio to the amp is purple and in connect position B3 on the radio and A3 on the amp. This wire was shorted to the ground somewhere. My son (keith04gp) and I fixed the problem we were having by replacing this purple wire with a new one that we ran.
