XTL5000 intermit power off

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TBerry1966
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Posts: 10
Joined: Tue Jul 23, 2013 6:58 am

XTL5000 intermit power off

Post by TBerry1966 »

I'm new here so please forgive me, and point me in the right direction, if this topic is redundant. I've gone back about a year on older posts and haven't seen it.
I have some XTL5000's (no remote control heads) that are intermitently powering off. When they do, they stay off (won't power up by turning vehicle off then restarting) unless manually powered up. Then they function fine...until the next time the issue occurs. I've also noticed they get unusually warm, some actually hot, even when idle (no TX for long periods).
Any ideas???
Jim202
Posts: 3609
Joined: Sun Sep 09, 2001 4:00 pm

Re: XTL5000 intermit power off

Post by Jim202 »

TBerry1966 wrote:I'm new here so please forgive me, and point me in the right direction, if this topic is redundant. I've gone back about a year on older posts and haven't seen it.
I have some XTL5000's (no remote control heads) that are intermitently powering off. When they do, they stay off (won't power up by turning vehicle off then restarting) unless manually powered up. Then they function fine...until the next time the issue occurs. I've also noticed they get unusually warm, some actually hot, even when idle (no TX for long periods).
Any ideas???



You may have a number of issues causing your problems. Let me make a couple of points and you can take it from there.

How old are these radios? Back a number of years ago, there was a problem with the firmware with the 05 control heads shutting off all by them selves. A service note was put out on this. I don't have access to them to find the one about this issue.

You might be wise to investigate just how the radios are wired. If you look in the install instructions, you will find that the ignition control wires need to be connected correctly. The yellow wire can be run to an ignition control. The small red wire needs to be connected to a hot 12 volts all the time. If not, you will find the radio will pull about 700 ma all the time the vehicle is shut off. This will kill the battery over a weekend.

You also might check on just how you have the software set in the radio. I have had issues with the selection under the ignition control. My radio did some strange things. I originally couldn't shut it off from the power button on the control head. I found that I needed to select I believe it was the "soft" selection. After that, I have never had an issue.

The last place I would check is the vehicle electrical voltage and the radio wiring. If you have a poor ground at the radio high current wire (heavy black wire) going to the vehicle frame, you could see some strange problems. Also you need to check the electrical ground at the battery. I am not talking about the battery post negative connection, but the ground wire going to the frame of the vehicle at the battery.

You should also measure the vehicle electrical system voltage. Measure the battery voltage with a digital meter before starting the vehicle. Try doing this first thing in the morning before even starting the vehicle for the first time. Write down what you find for voltage. Start the engine and measure the battery post voltage. Not on the connectors, but the actual posts. If you have side posts on the battery, well your not going to get to the posts. What I am looking for is poor connection between the post and the connector. Looking for how low the battery rest voltage is. An old battery (3 years or more) will have a lower rest voltage than a new battery.

An indication of an old vehicle battery is that the clock display will reset itself when you start the vehicle. Sort of an indication that the battery can't hold the voltage during the cranking of the engine. The first cold snap will also bring to your notice just how slow the engine is cranking. I have yet to make it over 3 years with the batteries I put in my vehicles. I buy top of the line large capacity batteries with 5 year warranty.

Then you start adding the electrical load. Turn on the headlights on low beam. Again measure the battery voltage. Go to high beam and measure the voltage. Turn on the whippers and measure again. Now turn on the heater full fan speed, measure the voltage. Turn from heat to air conditioning and measure again.

What your looking for is does the voltage hold or did it start to fall off. Generally if you have a bad alternator, you will find a point at where it can't supply enough output current. Another test is to put you digital meter in the AC mode and see just how much AC you have in the electrical system. Put the meter leads again on the battery posts. No load you should see maybe 20 to 50 millivolts of AC. Now do the load test and see if the AC meter reading goes way up. If you have a bad diode in the alternator, it will show up with a high AC volt measurement.

A point to mention here is the idle speed of the engine. Most vehicles today run the idle about 650 to 700 RPM. If your too low, the alternator can not put out enough current if it is turning too slow. A short story here that is true. I ended up with a brand new GE radio out of my trouble shooting way back in the early 70's. I got a call from one of the GE sales people I knew well. He was having a problem with all the new radios that were sold to the Vermont state police. He asked if I could I go up to the main radio shop and vehicle garage and take a look at what was going on. Made the trip and to make a long story short, the mechanics had turned down the idle on all the state police cars to about 550 RPM to save fuel. Problem was when the officer was out on a traffic stop the radio would go into a screech when it had incoming audio. With the headlights on high, the heater running and the big bubble gum light on the roof running, the battery voltage dropped like a rock. It went below the point the voltage regulator in the radio receiver could operate. The fix was a simple screwdriver adjustment and reset the idle back up to the 650 or so RPM. The alternator would put out enough voltage and everybody was happy. I guess a good intention doesn't always have the desired results.

I hope you have checked all the fuse connections and looked for any corrosion on any wire connections. This can also cause all sorts of strange issues. I find all sorts of splices in wires under the floor mats that are showing the blue-green oxidation where moisture has made it's way into the copper wires and splices.

My last comment is that the XTL series radios do run rather warm just in the receive standby mode. Seems like a poor engineering design in the radios where the electronics generates an excessive amount of heat doing nothing with no receive signal and no speaker sound.

Jim
TBerry1966
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Joined: Tue Jul 23, 2013 6:58 am

Re: XTL5000 intermit power off

Post by TBerry1966 »

I submitted a reply to Jim a few days ago, but I don't find it posted.
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