PM400 voltage alarm

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Posts: 47
Joined: Sun Jan 13, 2002 4:00 pm

PM400 voltage alarm

Post by kb2dem »

Is this a programmable option, beeps on transmit when my truck is running. Now also beeps on my power supply in the house

Posts: 1045
Joined: Tue Sep 04, 2001 4:00 pm

Re: PM400 voltage alarm

Post by Al »

Not programmable. Fixed by the voltage sensing hardware in the PM400. Try measuring the actual voltage at the PM400 power connector under a transmit condition. You may find that it's low enough to trigger the low voltage sensing circuitry. Solution if this is the case: check for high resistance in the power cabling or undersized conductors.
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Joined: Sun Mar 14, 2010 12:26 pm

Re: PM400 voltage alarm

Post by turtle9832 »

I had this same problem on a pm400. The radio was working fine in a vehicle. The radio was moved to another vehicle. The installer incorrectly installed the rear accessory cable for ign sense. The radio then was having low output power on tx along with the low voltage alarm on tx. Radio was removed and sent in. Depot replaced a board (I believe the depot report said it was a Q100 module or board). Radio was properly re installed and works fine now. The original installer related that the incorrect ign sense was not the cause of the board failure. The second installer said it was. If you need the part that was replaced verified, let me know.
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