Jag 725M Remote Issue

[Muxlow]

So!

Iv had a remote mount Jaguar 725M with a systems head mounted in the car for a while. Took it out to update some programming. Have another remote mount inside the house so just took the radio itself from the car, connected it to the setup in the house, programmed the radio and put it back in the car.

Problem

When i turn the radio on now i can hear the speaker make a pop type sound as if the radio just powered up (did this befor too) but the display dont turn on and i cant get the radio to go into program mode at all via the rear remote mount cable. When i take the remote mount and put it directly onto the radio as a front mount the display works. Tried 3 different remote mount cables and 2 system / 1 scan head and nothing when its connected as a remote setup.

What could cause this? Im unable to program the radio for somereason now. Only changes made were a few talk groups no other settings. The remote setup works with my Orion and did work with this radio.. but now it only works as a front mount setup

Also.. Does anyone know of a place i can order a front mount faceplate for the orions? Just need the "mounting bracket" the control head attaches to, for a front mount setup

 

[Doink]

aIt has been quite a while since I have seen this so bear with me. I believe the issue is related to fuses. As I recall the manufacturer fused some of the ground pins on the accessory connector, i.e. data ground, mic audio ground, etc. When a remote mount radio chassis doesn't have a good ground through either the main power connector, chassis mount to vehicle frame, or the antenna lead, it will draw ground current from the control head mounting or, as I have seen in one case, from the mic hook button. This current is to much for the control cable and that's why those leads are fused.

Anyway, to fix the issue you will need a copy of the manual to help find the blown ones. They are on the audio/logic board near where the accessory connector lands. There will be the typical decoupling caps and protection diodes and the fuses are mostly in that area. Some are on the top of the board and some on the bottom but I would recommend you consult the manual schematic and parts placement diagrams to ensure you find all of them. You could test the issue before opening up the radio by running a parallel ground wire from the control head to radio chassis but I wouldn't recommend this as permanent fix as it may be suitable for a power ground but not a data or mic audio ground.

And yes, the fuses are tiny little surface mount boogers and yes, there are two ground fuses in the control head as well. Again, consult the manual for locations and ratings