maratrac power up problem

[k0kjl]

I have a low band Maratrac in my company vehicle, the radio works great, the problem is if I let the truck sit over the weekend, when i get back in on Monday morning, the radio volume is at zero, the horn and lights button has been tripped, and the monitor light is on. I'm pretty sure I have it wired up right as far as what wires are hot all the time and which one goes to ignition control. Any help would be appreciated.

Thanks, Kyle

[wx4cbh]

On Maratracs, as with other Motos, but especially Maratracs, it's critical that the green wire and the large red B+ wire are connected to the same source so that there's no voltage difference between them that the radio can detect. The ground needs to be a demonstrably good one, too. As to the problems you describe, Maratracs do the Reset-to-zero_H/L_Monitor thing when the voltage drops below a certain level for a period of time determined by the particular Maratrac's anal requirements, and then you crank or attempt to crank the vehicle. If you hit the HOME key after cranking, the radio should return to its home channel, but the H/L and MON will probably need to be toggled back to normal. This is a common trait on things like fire trucks and ambulances that have a master battery disconnect or master switch that kills the voltage to the Maratrac.

Over the years, I've seen this reset thing on my own Ms when the battery decides to go into a gradual crapout spiral, the connections on the battery ground cable on the truck get corroded, and when the installation connections get less than required attention. Bottom line is that Ms get pissy over low voltage or voltage differences on the green and Red power leads or insufficient grounds, but all this doesn't mean there's not an internal radio or control head problem. Go for the installation wiring and the condition of the vehicle's wiring/battery first, then if all is good there, the radio could use a look.

[k0kjl]

thank you, i'll give it a try.