XTL 2500 no audio (fixed)

[olderookie]

I was working with and XTL 2500 that was losing its audio, and would not be able to transmit. I moved this radio from one vehicle to another, using same wiring points.

I checked voltage and had 12v or more at radio head and 12v at drawer in the trunk. It would get worse when the vehicle was not running and would also occur with the lights on. I tried to load the vehicle down with all the accessories and replicate the problem. I still had a working radio.

I then used a old type manual alternator tester and loaded down the electrical system. I was then able to replicate the problem. I had battery replaced and seemed to fix the issue. well a week later same issue.

So I get the car and do everything I can to replicate, still seems to work fine while testing. 12v at radio head and 12v at drawer. I left radio on and as many accessories as I could for an hour or more. Originally it would happen within minutes of shutting car off.

so everything is telling me I have a voltage drop issue? I am torn at this point? So I said to myself, Self run a complete new power lead to the radio head!

Ok so I take the few minutes to run another wire from the battery to the radio head and low and behold I now have a lot more voltage when the car is running, in the area of 14v. I did get one quick reading before all this of 10v at radio head. I have no idea where the original power lead was tapped from but now the radio works perfectly.

I though I would share this as the radio never shut off and by all outward appearances should have been working but it just didn't have enough power to operate properly. I know the newer radios are less tolerant to deviations in voltage so keep that in mind when trouble shooting these great wiring messes that we inherit and when a description is "radio not working"

[Jim202]

I was working with and XTL 2500 that was losing its audio, and would not be able to transmit. I moved this radio from one vehicle to another, using same wiring points.

I checked voltage and had 12v or more at radio head and 12v at drawer in the trunk. It would get worse when the vehicle was not running and would also occur with the lights on. I tried to load the vehicle down with all the accessories and replicate the problem. I still had a working radio.

I then used a old type manual alternator tester and loaded down the electrical system. I was then able to replicate the problem. I had battery replaced and seemed to fix the issue. well a week later same issue.

So I get the car and do everything I can to replicate, still seems to work fine while testing. 12v at radio head and 12v at drawer. I left radio on and as many accessories as I could for an hour or more. Originally it would happen within minutes of shutting car off.

so everything is telling me I have a voltage drop issue? I am torn at this point? So I said to myself, Self run a complete new power lead to the radio head!

Ok so I take the few minutes to run another wire from the battery to the radio head and low and behold I now have a lot more voltage when the car is running, in the area of 14v. I did get one quick reading before all this of 10v at radio head. I have no idea where the original power lead was tapped from but now the radio works perfectly.

I though I would share this as the radio never shut off and by all outward appearances should have been working but it just didn't have enough power to operate properly. I know the newer radios are less tolerant to deviations in voltage so keep that in mind when trouble shooting these great wiring messes that we inherit and when a description is "radio not working"

One issue you need to be aware of is how you supply voltage to the control head. There should be both a small red wire and a yellow wire. The red wire needs to have +12 volts on it all the time regardless if the vehicle is running or not. The yellow wire can be run through an ignition controlled feed.

If you try to switch the red wire +12 volts, the radio goes into a funny mode. It will pull about 700 ma all the time until you apply +12 volts to the yellow wire again. This will kill the vehicle battery over a day or two.

This can be found in the installation manual of the newer radios.

My guess in your case is that you had a poor fuse connection or a bad splice some place in the yellow wire supplying the +12 volts to the control head. These radios all work with microprocessors in both the control head and radio. Low voltage will make them do all sorts of strange things.

Glad you found the problem.

Jim