I tried to add an audiopipe gm300 amplifier to my kenwood head but, when i turn on the amp, the head unit turns off and i have to reset it.
Did you bench test the amp first? When the deck turns on, the amp should turn on also. Unless there's a problem with the amp, it's likely you have something wired wrong. Double check your wiring.
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My ex once told me I have a perfect face for radio.
I cheked the amp, it turns on ok, i double check the speaker wiring.
With the amp off, the head unit works nice but when the amp is turned on, the head unit goes off again
thats a low model kenwood which doesnt have a seperate aux output just for subs it just has front and rear. and im not sure if it has front output. the amp might be drawing to much power from the remote wire. i had this problem with a my kenwood x789. check your remote and patch cords. if that doesnt work your internal amp on the hu is clipping out so u dont fry your hu. that is caused by to much power being drawn or bad wireing.
The remote lead and rca's should be the only connections you have from the headunit to the amp. Disconnect the rca's. The remote output on the headunit is probably rated at around 500 mA (most are, but your manual should say), which is plenty to power up 2 amps. Install a 500 mA fuse inline on the turn on lead and try to power up the amp. See if the fuse blows. If the fuse does not blow, chances are you have a problem with the deck. If the fuse does blow, chances are it's with the amp. Just to be sure, try hooking the amp's remote wire to the red wire on the Kenwood. This way, the amp should turn on when you turn on the key. If this works, and you can plug in the rca's with no problems, then you've identified the deck as the culprit.
My bet is there's a problem with the deck's remote out circuit.
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My ex once told me I have a perfect face for radio.