QuestionQUESTION: I'm trying to replace the stock AM/FM/Cassette radio with Infinity speaker system in my 1997 Dodge Grand Caravan with the Sony CDX-GT210 AM/FM/CD player.
However, when I connect up the new unit, not all speakers work. Only the dash speakers and the far rear tweeters work. After doing some research, I discovered that I somehow need to activate the Infinity amplifier. I also discovered that the little black wire that was plugged into the old unit is somehow the key to activation.
I found the 327001.pdf file from www.installdr.com which directs you to connect the new stereo's ground to the amp activation wire instead of ground. However, nothing I seem to do will activate the amp. I tried connecting the new stereo's ground to the wire and nothing. I connected the wire directly to ground and nothing. I connected the wire to one of the speaker's common and nothing. Five hours shot. Any ideas?
ANSWER: I think the amp needs two power lines. One comes through a fuse directly from the battery. The other comes from the head unit and is the turn-on lead. So, check that out.
If you have a vom, check the amp for both 12v getting to it.
Hope this helps.
C
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QUESTION: On another website, I found a clue that the new stereo's power antenna connection may have to be connected to the car's radio harness for the amp to work. Do you know if that is true? I left that connection out since the van has no power antenna.
ANSWER: Yes, that is true. Good point that I did not catch.
But I can't offer you a suggestion; try grounding it first - carefully. If it sparks, it has voltage on it. Best to check it with a vom first. Then you will know. If it has 12v on it, it may be power antenna feed; or it may be amp feed, as stated before.
In the long run, you may have to get dirty - using vom check out all the wiring so you know positive certain where each wire goes.should go and where everything is mounted. It is laborious but the only way for tough ones.
If the dead speakers are not getting power after all this, trace the wires back to the amp; then you will know where it is located and you can, as before, check it out for power, etc.
Hope this helps.
C
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QUESTION: I've got this figured out. Basically the original head unit powers the amp, providing both hot (+12v) and ground. The +12v was provided from the head unit to the amp using one of the normal 8 pin connectors (the line possibly identified as ant). The ground was provided to the amp from the head unit using a single wire separate from the multi-pin connectors (simple spade connector).
So, if the new aftermarket head unit has a +12v output that is active whenever the stereo is on, then you can simply connect that output (sometimes a power antenna output) to the amp's +12v, and then ground the single ground spade connector. When the stereo turns on and powers the "antenna" it will actually be activating the amp.
But, if the new stereo does not have a +12v output, or the antenna output is on only when the stereo is in tuner mode (but not in CD or aux mode), then you won't properly be powering the amp. This was my situation.
So, I simply wired the amp ground wire to ground, and wired the amp +12v to the +12v accessory supply to the new stereo. The down side is that the amp will be powered whenever the van is on or in acc mode (even if the stereo is off). The good news is that I'll get bass (amp) when listening to CD, tuner, or aux!
AnswerIf it is a good amp, it won't hurt to be ON all the time. They are biased such that when there is no signal they only draw a few milliamps and produce virtually no heat.
Good job. Thanks for being creative in your solution and having the wisdom to solve it on your own.
c
