Radio reset - Battery dying?

[cosmichobo]

G'day,

For the past few months (ie probably 3 or so), the radio/cassette keeps resetting itself.

It doesn't happen every time you start the car up, but especially first thing in the morning - ie after 8+ hours of non-use.

The time resets to 1:00, and saved radio channels etc disappear.

Now, we assumed it was the battery, which incidentally is 3 years old... but - the car itself has only ONCE in that time period sounded like it was struggling to start.

I haven't dug out the multimeter yet to see what volts its making under crank, but - is there anything else that could be going on here?

cheers

cosmic

[le.vinh.zr]

I'm guessing its the constant wire that may be faulty, you would need to take the radio out and have a look.

This should be the wire your looking for:

http://ccs.exl.info/carwires.html#TOYOTA

Blue/Yellow

Vinh

[Ozzcaddy]

I have the same problem with the radio/cassette in the Camry I just purchased. After setting the Clock and setting a particular radio station,

once I either turn the radio off or the ignition, the clock resets back to 1.00, and depending on the delay in turning the radio back on, the preset radio station is also lost. I shall check that power(memory)wire.

I have the download of the various manual (Body Electrical) from the US site, so hopefully the wiring will be the same.

Thanks Vinh

The download manual is 99EWD Wiring

Edited August 9, 2010 by Ozzcaddy

[Ronnyboy]

This should be the wire your looking for:

http://ccs.exl.info/carwires.html#TOYOTA

Blue/Yellow

Vinh

This is a really handy Website for DIY car Audio installtion.....

[Ozzcaddy]

I have the same problem with the radio/cassette in the Camry I just purchased. After setting the Clock and setting a particular radio station,

once I either turn the radio off or the ignition, the clock resets back to 1.00, and depending on the delay in turning the radio back on, the preset radio station is also lost. I shall check that power(memory)wire.

I have the download of the various manual (Body Electrical) from the US site, so hopefully the wiring will be the same.

Thanks Vinh

The download manual is 99EWD Wiring

A new battery yesterday resolved the problem with the clock and pre-set radio stations losing memory. All OK now.

[Talbit]

I have the same problem. A new battery fixed it as well but after a year or so it started again - even though the battery was in perfect condition. I then got a little more serious and cut the "Constant" (memory) wire at the back of the radio connector then ran a direct wire from the battery positive to the "Constant" wire. I thought it was okay but it still does it. I think there is something more serious with the memory system because having even an average battery shouldn't give you this fault. I might try and get a circuit diagram for the radio and see if I can figure it out from that but having already looked at the radio I noticed it is all surface mount and very difficult to see, let alone fix. I'm keen to know if you still have the problem. Mine doesn't have a clock in the radio but is a separate display. It doesn't lose time. I have a Dec 2000 CSI MCV20R

Regards Talbit

Edited August 26, 2010 by Talbit

[Ozzcaddy]

I have the same problem. A new battery fixed it as well but after a year or so it started again - even though the battery was in perfect condition. I then got a little more serious and cut the "Constant" (memory) wire at the back of the radio connector then ran a direct wire from the battery positive to the "Constant" wire. I thought it was okay but it still does it. I think there is something more serious with the memory system because having even an average battery shouldn't give you this fault. I might try and get a circuit diagram for the radio and see if I can figure it out from that but having already looked at the radio I noticed it is all surface mount and very difficult to see, let alone fix. I'm keen to know if you still have the problem. Mine doesn't have a clock in the radio but is a separate display. It doesn't lose time. I have a Dec 2000 CSI MCV20R

Regards Talbit

Everything is still going good with clock (in radio) and pre-set stations. The battery has only been in almost 2 weeks, so not expecting any problems.

Your problem sounds more internal as you said, seeing you put direct power to the radio from the battery. I haven't seen any circuit diagrams for the radio itself. Maybe a enquiry with a radio installer may add some light to your problem.

[Talbit]

I have the same problem. A new battery fixed it as well but after a year or so it started again - even though the battery was in perfect condition. I then got a little more serious and cut the "Constant" (memory) wire at the back of the radio connector then ran a direct wire from the battery positive to the "Constant" wire. I thought it was okay but it still does it. I think there is something more serious with the memory system because having even an average battery shouldn't give you this fault. I might try and get a circuit diagram for the radio and see if I can figure it out from that but having already looked at the radio I noticed it is all surface mount and very difficult to see, let alone fix. I'm keen to know if you still have the problem. Mine doesn't have a clock in the radio but is a separate display. It doesn't lose time. I have a Dec 2000 CSI MCV20R

Regards Talbit

Everything is still going good with clock (in radio) and pre-set stations. The battery has only been in almost 2 weeks, so not expecting any problems.

Your problem sounds more internal as you said, seeing you put direct power to the radio from the battery. I haven't seen any circuit diagrams for the radio itself. Maybe a enquiry with a radio installer may add some light to your problem.

A friends' here at work has done it at least once. So I'm convinced it's not just my radio. I contacted a tech at Fujitsu Ten and he hadn't heard of it before. I'm in the process of getting a circuit.

Talbit

Ok, here's an update. I contacted Fujitsu Ten and one of the techs emailed me back saying it's a known problem. He sent me a small portion of the circuit. IC500 needs to be replaced. I'm a tech so will have a look at it today. It's a 5 volt regulator (a special type it seems). But beware that my radio might be a little different to yours because my clock is separate. My guesse is if you've had this problem once then it will happen again.

I'll keep you posted.

Regards Talbit

And another update... I can't find IC500 on the PCB so I've taken some photos and will contact Fujitsu Ten on Monday. I think I have a different radio to what he thinks I've got. If I can be sure of my model number then I'll buy the circuit off him. More later.

Regards

Talbit

Edited August 29, 2010 by Talbit

[Talbit]

I have the same problem. A new battery fixed it as well but after a year or so it started again - even though the battery was in perfect condition. I then got a little more serious and cut the "Constant" (memory) wire at the back of the radio connector then ran a direct wire from the battery positive to the "Constant" wire. I thought it was okay but it still does it. I think there is something more serious with the memory system because having even an average battery shouldn't give you this fault. I might try and get a circuit diagram for the radio and see if I can figure it out from that but having already looked at the radio I noticed it is all surface mount and very difficult to see, let alone fix. I'm keen to know if you still have the problem. Mine doesn't have a clock in the radio but is a separate display. It doesn't lose time. I have a Dec 2000 CSI MCV20R

Regards Talbit

Everything is still going good with clock (in radio) and pre-set stations. The battery has only been in almost 2 weeks, so not expecting any problems.

Your problem sounds more internal as you said, seeing you put direct power to the radio from the battery. I haven't seen any circuit diagrams for the radio itself. Maybe a enquiry with a radio installer may add some light to your problem.

A friends' here at work has done it at least once. So I'm convinced it's not just my radio. I contacted a tech at Fujitsu Ten and he hadn't heard of it before. I'm in the process of getting a circuit.

Talbit

Ok, here's an update. I contacted Fujitsu Ten and one of the techs emailed me back saying it's a known problem. He sent me a small portion of the circuit. IC500 needs to be replaced. I'm a tech so will have a look at it today. It's a 5 volt regulator (a special type it seems). But beware that my radio might be a little different to yours because my clock is separate. My guesse is if you've had this problem once then it will happen again.

I'll keep you posted.

Regards Talbit

And another update... I can't find IC500 on the PCB so I've taken some photos and will contact Fujitsu Ten on Monday. I think I have a different radio to what he thinks I've got. If I can be sure of my model number then I'll buy the circuit off him. More later.

Regards

Talbit

Almost there. Should get it going tomorrow and then it's keep the fingers crossed.

Talbit

[Talbit]

I have the same problem. A new battery fixed it as well but after a year or so it started again - even though the battery was in perfect condition. I then got a little more serious and cut the "Constant" (memory) wire at the back of the radio connector then ran a direct wire from the battery positive to the "Constant" wire. I thought it was okay but it still does it. I think there is something more serious with the memory system because having even an average battery shouldn't give you this fault. I might try and get a circuit diagram for the radio and see if I can figure it out from that but having already looked at the radio I noticed it is all surface mount and very difficult to see, let alone fix. I'm keen to know if you still have the problem. Mine doesn't have a clock in the radio but is a separate display. It doesn't lose time. I have a Dec 2000 CSI MCV20R

Regards Talbit

Everything is still going good with clock (in radio) and pre-set stations. The battery has only been in almost 2 weeks, so not expecting any problems.

Your problem sounds more internal as you said, seeing you put direct power to the radio from the battery. I haven't seen any circuit diagrams for the radio itself. Maybe a enquiry with a radio installer may add some light to your problem.

A friends' here at work has done it at least once. So I'm convinced it's not just my radio. I contacted a tech at Fujitsu Ten and he hadn't heard of it before. I'm in the process of getting a circuit.

Talbit

Ok, here's an update. I contacted Fujitsu Ten and one of the techs emailed me back saying it's a known problem. He sent me a small portion of the circuit. IC500 needs to be replaced. I'm a tech so will have a look at it today. It's a 5 volt regulator (a special type it seems). But beware that my radio might be a little different to yours because my clock is separate. My guesse is if you've had this problem once then it will happen again.

I'll keep you posted.

Regards Talbit

And another update... I can't find IC500 on the PCB so I've taken some photos and will contact Fujitsu Ten on Monday. I think I have a different radio to what he thinks I've got. If I can be sure of my model number then I'll buy the circuit off him. More later.

Regards

Talbit

Almost there. Should get it going tomorrow and then it's keep the fingers crossed.

Talbit

My cassette/radio is operational again after replacing several components.

Remember my cassette/radio has a separate clock so the internals might be different to yours. My radio model number is 86100-YC260. It’s on the sticker on the back.

I replaced the following parts…

IC500 was a S81250HG – a 5 volt regulator. This is a very small surface mount device. You can recognise it only by it’s marking ‘RD’. This was supposed to be the main culprit. I replaced it with a HT7550 (Farnell 142-0876)

C515 is a 4.7uF/25 volt electro. I replaced it with a Farnell 918-9629

C408 & C513 are both 10uF/16 volt electros. I replaced them with Farnell 945-2192.

I also replaced the Supercap C510 .047F/5.5 volt with RS Components 295-895. But you can also get these from Jaycar. All the components are in the same vicinity. Do not try and do this yourself unless you know what you are doing. But if you tell your local radio tech what to do then I’m sure he’ll work it out.

But remember I’m not sure if the fault has been fixed. Only time will tell.

Good luck.

Talbit