Okay, so I have a 1999 Mazda Protege with a stock FMS cassette unit and I bought a Pioneer DEH2200UB CD/USB/MP3 unit and installed it myself. I know I will upset some experts out there by telling you I tapped into the original Mazda harness using t-taps to connect the Pioneer unit. After I tapped the new harness in, I checked the cassette and it still played fine. Then I plugged the new harness into the Pioneer unit and the Pioneer unit worked fine. Then I tried to play a tape in the cassette unit and no sound came out from the speakers. Just to be sure I disconnected the Pioneer unit and tried the cassette again and it worked.
So why does the cassette unit NOT work when the Pioneer is connected to it? Is there some kind of jumper or other connection I can make to let the Pioneer "unblock" the OEM unit? Note, all these are done with one unit powered off and one powered on (otherwise I blow the fuse).
Please don't be too harsh with me, I just (apparently) don't know what I am doing and I need some help.
Thanks,
jm
