battery consumption with Power OFF

[ray7278]

I have a strange problem with a GP388. With the Power OFF, the battery goes down (unload battery)
The GP388 uses energy with the switch power off !!! With the power on, battery life seems to be less.
I also tried with new battery, same !!!
With an another GP388 and this 2 battery, there is no problem
Does someone know this kind of problem ?
Ray

[Zack08]

Does the PA always have power running to it? I've heard that some radios with unswitched PA power will do this if the PA goes bad, but I honestly cant remember which radios this affected.

[ray7278]

Thanks for your answer Zack08
I'm not sure to anderstand PA. PA = Power Amplifier ? (or quick charger ?)
How can I see if PA goes bad ?
What can I do to verify ?
Does someone had this kind of problem ?

[Zack08]

Yes, by PA I meant the RF power amplifier. I just looked at the schematic for the 388, and it looks like the RF PA, the audio PA and a 3.5v regulator are all fed by unswitched B+, so these are all possible culprits.

The schematic shows that the 3.3V regulator feeds an internal lithium ion battery. I'd check this battery first to make sure that its okay, because maybe your power draw is coming from the regulator constantly trying to keep it charged.

Other than that, I've never worked on those radios, so you'll have to turn to somebody else if you need to know how to test the other stuff.

Good luck!
-Zack

[ray7278]

Thanks Zack08
I see it's very technical and it's going to be very difficult for me. I really don't know how to check this internal battery !!!
If someone who knows GP388 could help me !!!
Ray

[Zack08]

Yeah, I wasn't sure what your level of experience was with this kind of stuff. I can tell you from personal experience that if you dont feel comfortable, its probably best to find somebody who does.

If you ask around, maybe you can find one of our members who would be willing to look at it for you.

[Mikey]

I had this happen to a HT1250 and it was a bad PA Unit. But you could physically feel the radio case get hot when the switch was off.

[ray7278]

Yes, I can physically feel the radio case get a little hot when the switch was off but not so much.
It's more hot with the power on compared with an other GP388.

Thanks to help because I really lost !

[ray7278]

I tried again to let the GP388 with the power off and i can feel the radio case hot. If I take off the battery, the metal is hot
Mikey, what did you do for your HT1250 ? Did you change the PA unit ?

Thanks to everybody to help me for this problem

[Mikey]

Yup, i sent it to the Depot and they Changed the PA unit for me since it was still under Warranty.

[ray7278]

So If I anderstand, it's a hardware problem of my GP388 and I need to change the Power Amplifier unit ?
Does someone know if it's expensive and how it's possible to do it ?
Ray

[Zack08]

It is possible to change the PA, but unless you have experience with surface mount rework, then I dont recommend doing it yourself. Not only is the RF PA a surface mount device, but I believe it is also covered by a surface mount shield that you must carefully remove.

[ray7278]

Thanks Zack08, I see it's not for me. Do you know if it's expensive with a Motorola dealer ? I think it's the only one way for me !!!

[d119]

Thanks Zack08, I see it's not for me. Do you know if it's expensive with a Motorola dealer ? I think it's the only one way for me !!!

Cheapest way to do this would probably be flat-rate via the depot. Otherwise you're not only paying the cost of the part, but also the labor to remove the bad unit, install the good one, and then do a full alignment and test, HOPING that the PA was actually the problem.

Send the thing to the depot.

[ray7278]

Thanks d119,
do you think it could be something else and not the PA ?

[RADIOMAN2002]

I send an average of one to two out a month to Moto-mexico. Seems to be a common problem, most of the defective units were built in 2003 and 2007. I did have a brand new one right out of the box bad, built in 11/08. I have heard that keying up the radio without the antenna is a major reason, can't confirm that. BTW it is a PITA to replace, unless you have hot air machinery, I wouldn't try it. What is the build date on your radio or the serial number. I would like to start a list to maybe get Motorola to repair radios beyond their warrante period.

[GlennD]

Looking at the flat rate list dated 9/2/09 it looks like $284 for a HT1250.