Batboard

I have programmed the radio several times, combed the software for mistakes, double checked the private line settings, and confirmed the mic grounding, yet I am still getting carrier sq. Any suggestions?

I don't know your type control head, but have you checked the pinouts between the cable & head, or the mic hangup box & the head / cable. I don't have a manual or any kind of info on the Maratrac wiring.

Yes it sounds like the ctcss (pl)
is not working in the rx of the radio. Test and change the damaged components.This is
board level repairs. Put radio on service
monitor and send pl to rec. and see what comes up.

When you say you grounded the mike, did you use a vehicle ground or the jumpered lead of of the cable going to the head. There is a 2 pin or two wire connector depending on the head type, (most familiar with HHCH units) You must either connect this for your mike ground or you can jumper it with a loop or plug with a simple loop. Then it should allow for pl only and monitor by the buttons

If you have an A7 head make sure the jumper is in the VIP connector.
You can find the pinouts on batlabs

I'm not sure what P.L. you are using but I have run into the same trouble with tone 118.8 it is easly falsed by 60hz AC line noise... I have seen this many times on the bench using an R2000 and a good Astron RS 50. I would program in another P.L. and no problems... Good Luck!

The PL I am using is 127.3 I know the mic is grounded because I have it programmed to stop scanning off hook. I am totally baffled. This occurs on 2 of my Maratrac radios, so the odds that that are both broken with the same problem is slim to none. I called Motorola and we went through this over the phone. They said they had "the books out" and found nothing else to do. Meanwhile, we continue to get horrible skip off of Lake Michigan.

Are you on Lowband ?

I am on VHF 150-160 range.

Try disabling Priority scan and then see if your problem goes away. I have a hunch, seems to be a problem with these radios.