Question about Pioneer SX-255R Receiver

1 Answer

NEEED A SCHEMATIC

OVERLOAD WRITTEN ON DISPLAY AND OUT PUT TRANSISTORS VERY HOT.EVEN WHEN NO SPEAKERS ARE CONNECTED

Posted by on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    Hot-Shot:

    An expert who has answered 20 questions.

    Corporal:

    An expert that hasĀ over 10 points.

    Mayor:

    An expert whose answer gotĀ voted for 2 times.

  • Expert
  • 86 Answers

Check your fuses that might one problem, an the second one check the heat sink on the receiver witch would hold the heat in side the amp to remain hot

Posted on Nov 07, 2008

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Technics sa-dx1050 overload


if any one of the channels was shorted out, even momentarily, that channel's output transistors would likely be blown causing it to stay in protection mode. (or overload as you put it). Time to visit the repair shop.

Jul 23, 2012 | Technics SA-DX1050 Receiver

Tip

My Pioneer displays Overload


Overload is displayed when the amp draw is excessive, and can be caused by different faults.
when Overload is detected, the protection circuit will shut down the unit to prevent further damage.

The first thing to try is hard reset. Shut down the unit for about one hour to drain power completely.
This can fix minor problems that can cause overload, for example electrostatic charge accumulation on internal capacitors.

If that does not fix the problem, then you must find the fault.

Overload can be caused by shorted speakers, wrong impedance speakers, or by a contact on speakers wiring.
Check speakers connection and test different speakers with 6, or better 8 Ohms impedance.

Another test can be done by unplugging all speakers, and reconnecting and testing them one at a time, at a very low volume.

If the speakers are OK, then preamp, shorted input/output connectors, main power supply or faulty output transistors can draw too much amps causing overloading.

In that case it is recommendable contacting Pioneer at the number listed on the owners manual.

on Jun 22, 2009 | Pioneer VSX-D608 Receiver

1 Answer

I have a panasonic SA-HE70 amplifier and all it keeps doing is scrolling OVERLOAD.... why??


hi,.

First of all remove all the speaker connections from the amplifier. After that power the amplifier and check that it gose Over load ( protection ) show or not . if not, then any of the speakers or its wiring have some problem. If so the reconnect the speakers one by one and switch ON the amplifer and check.find out on wchi speaker it shows lover load.


if the amplifer shows overload even after removing the speakers then you have to check the amplifiers hardware.

Also added the procedure how to check the amplifier satge. You should have a good knowledge in electronics to do the following. Also need testing instuments.


AV receivers shows protect mode , when there is a hardware fault in side it. Its a warning that some thing is wrong.
Normally AV receivers show this when any of the output amplifier have some problem. there are five amplifiers in this AV receiver. This problem occur when the output diver transistors of any of the amplifier become shorted. if the output transistor get shorted this will lead to flow of current through the speakers. To prevent this there is a protection circuit for each channels. One combined output of this protection circuit is connected to the system control. when the any of the output amplifier fails, the protection circuit detects it and switch of the speaker and sent data to the system control. when the system control get this data it will give a warning to the customer through display that PROTECT.
You have to check the amplifier.

For that you need digital multimeter,soledring iron screwdrivers etc

Open the amplifier , then power it on. connect the negative terminal of the multimeter any where in the chase( metal body of the amplifer). then connect the positive terminal to all the output transistors emitter pin one by one . the voltage should be bellow 0.5V. If any of the emitter of the transistor shows voltage more than 0.5V., then that amplifier stage is faulty. Remove the transistors and check it. if it is shot then replace with a new one.
after replacing the transistors do not power up the amplifier directly from the main. You have to put a bulb of 60 watts in serial.
You can do this easily remove the mains fuse. put the bulb in a holder. now you have to wire from the holder. connect one of it to the one end of the fuse holder and the other wire to the other end of the fuse holder. Why using a bulb is, if there is any further problem in the amplifier stage on which the transistors replaced, there is a possibility of the new transistor get damage. if we use a bulb in serial with its mains supply ,when any overload in the amplifier occur the bulb will drop the current, by lighting itself.
After connecting the bulb in serious power on the amplifier. watch the bulb. It should light for one or two second and go dim . if so check the display, is there is protect mode is on or not . if not and come back to normal operation ,then remove the power , remove the bulb insert fuse and check
connect the power and check.
If the bulb shows bright light then there is some component also faulty in the same amplifier. after removing the power you have to check again the amplifier stage of which the transistor is replaced, for any other faulty components

OK

Sep 19, 2011 | Panasonic SA-HE70 Receiver

1 Answer

Pioneer vsx 515 overload and shuts down what can i do to fix this problem.


hi,
First of all remove all the speaker connections from the amplifier. After that power the amplifier and check the overload (protect) show or not . if not, then any of the speaker is damaged or you have to check the impedence of your receiver and speakers. It will be written on the rear side of both receiver and speakers in ohms. PIONEER recommend to connect 8 ohms speakers in to this AV receiver. If you are using 6 ohms speakers you have to do some setting in the AV receiver.For that do the following

1. With the receiver in standby, press STANDBY/ON while holding down the SPEAKER IMPEDANCE button.( Each time you do this, you switch between the impedance settings: )


SP 6 OHM - Use this setting if your speakers are rated at 6 Ohms

SP 8 OHM - Use this setting if your speakers are rated at 8 Ohms or more


You are not able to connect speakers with impedence bellow 6 Ohms with this receiver. Becuse the AV receivers impedence range is 6 - 16 Ohms.
If then also it shows protect you have to check the amplifiers hardware.

AV receivers shows protect mode , when there is a hardware fault in side it. Its a warning that some thing is wrong.
Normally AV receivers show this when any of the output amplifier get some problem. there are six amplifiers in this AV receiver. May occur when the output diver transistors of any of the amplifier become shorted. if the output transistor get shorted this will lead to flow of current through the speakers. To prevent this there is a protection circuit for each channels. One combined output of this protection circuit is connected to the system control. when the any of the output amplifier fails, the protection circuit detects it and switch of the speaker and sent data to the system control. when the system control get this data it will give a warning to the customer through display that PROTECT.
You have to check the amplifier.
for that you need digital multimeter,soledring iron screwdrivers etc
open the amplifier , then power it on. connect the negative terminal of the multimeter any where in the chase( metal body of the amplifer). then connect the positive terminal to all the output transistors emitter pin one by one . the voltage should be bellow 0.5V. If any of the emitter of the transistor shows voltage more than 0.5V., then that amplifier stage is faulty. Remove the transistors and check it. if it is shot then replace with a new one.
after replacing the transistors do not power up the amplifier directly from the main. You have to put a bulb of 60 watts in serial.
You can do this easily remove the mains fuse. put the bulb in a holder. now you have to wire from the holder. connect one of it to the one end of the fuse holder and the other wire to the other end of the fuse holder. Why using a bulb is, if there is any further problem in the amplifier stage on which the transistors replaced, there is a possibility of the new transistor get damage. if we use a bulb in serial with its mains supply ,when any overload in the amplifier occur the bulb will drop the current, by lighting itself.
After connecting the bulb in serious power on the amplifier. watch the bulb. It should light for one or two second and go dim . if so check the display, is there is protect mode is on or not . if not and come back to normal operation ,then remove the power , remove the bulb insert fuse and check
connect the power and check.
If the bulb shows bright light then there is some component also faulty in the same amplifier. after removing the power you have to check again the amplifier stage of which the transistor is replaced, for any other faulty components.
ok

Jul 27, 2011 | Pioneer VSX-515 Receiver

2 Answers

My technics receiver stop playing, and display an overload message. what do you believe the is the problem ?


If you are getting an overload problem, it indicates an output load issue. Turn receiver off! remove speaker wires from the back of the unit, this will reset the protection circuit. Now power up and turn your volume right down, If the word overload stays off it means there is a short in the wire or speaker. But! if the word overload comes on "even with the wires and speakers dis-connected" it indicates a short in one or more of the audio output ic's or transistors.

Mar 17, 2011 | Technics Audio & Video Receivers

2 Answers

Have recently had an "overload" displayed. Have


HI:
Usually receivers go into overload due to a bad speaker make sure you disconnect the speakers also to make sure its overloading from a bad speaker. If the unit still shows overload even with all speakers disconnected, then your main amplifier output has a short usually a shorted output transistor is the cause. Unplug the speakers one at a time to and turn the unit on after disconnecting one of the speakers , to determine which speaker is at fault.

Jan 23, 2011 | Panasonic SA-HE200 Receiver

2 Answers

Yamaha AX 550 amp blows fuse when power switched on,


Generally speaking, an amp protects itself from heat, shorts and overloads.

Overloads can be from excessive periods of high output and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'naked'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced hands-on tech.

Jan 17, 2011 | Audio & Video Receivers

1 Answer

Every time i torn it on it gos on protect mode ?


The most often external cause of protection overload is shorts in the speaker wiring or a speaker with a shorted voice coil; either of which is placing an unusually heavy load on the amp that is connected to that shorted condition. Anything that will lower the impedance will cause the overload. In your case you should check all the speakers to see if anyone of them is not working or is way low in output. This will give you a clue indicating that speaker may be in trouble.

Another easy way to check for external problems is to disconnect all speaker wires at the back of the amp. Then, run the volume up with no loads and see if it still fails - which would mean there is an internal problem. If it is okey with no loads connected, then connect only one at a time and see if just one speaker line it the cause.

The most common cause from internal problems is when the amp gets old and tired the silicon grease washer on the output transistors gets dried out and goes hard. It no longer is a good thermal conductor for getting heat from the output transistor into the heat sink it is mounted on. You can check this by putting your finger on the output transistors after the system shuts down; if any one of them is really hot to the touch that is a good indication. The easiest way to correct for that is replace the amp/receiver. Repair often costs as much a good receiver. Or, if you know how to regrease them you can do it by yourself for a few dollars. Lots of labor, though, because the transistors must be desoldered and pulled off; old grease removed, mica washers replaced and regreased with silicon heat grease.

Feb 12, 2010 | Sony Audio & Video Receivers

1 Answer

VSX-D608 Overload and shutdown


Overload is displayed when the amp draw is excessive, and can be caused by different faults.
when Overload is detected, the protection circuit will shut down the unit to prevent further damage.

The first thing to try is hard reset. Shut down the unit for about one hour to drain power completely.
This can fix minor problems that can cause overload, for example electrostatic charge accumulation on internal capacitors.

If that does not fix the problem, then you must find the fault.

Overload can be caused by shorted speakers, wrong impedance speakers, or by a contact on speakers wiring.
Check speakers connection and test different speakers with 6, or better 8 Ohms impedance.

Another test can be done by unplugging all speakers, and reconnecting and testing them one at a time, at a very low volume.
No more than two 4 Ohms speakers can be connected to the unit, or you will get overload.

If the speakers are OK, then preamp, shorted input/output connectors, main power supply or faulty output transistors can draw too much amps causing overloading.

In that case it is recommendable contacting Pioneer at the number listed on the owners manual.

Jun 22, 2009 | Pioneer VSX-D608 Receiver

1 Answer

I have a Technics SA-GX470. It displays the last selected input and then overload turn power off. The owner admitted running the volume pretty high and it would go into overload and after power off and...


I have not solved it yet. I did find a similar schematic of another model. I have gone over the entire board checking connections first. What I see is the minus 14 volt regular running very hot. The voltage is OK but there is something drawing a lot of current. The plus side is cool. I am in the process of looking at all the loads on it but believe it may be the main power module. This unit has two modules with the main one for the left and right speakers and another that is for the center and surround speakers. It is cool and guess the the main one may be bad. Panasonic is the only source for this one and that is doubtful. The prices I have found is around $60 and a little expensive to buy and just try. I am going to make sure it is the problem before I recommend they spend that much up front. Technics is a low end Panasonic product and I have found this to be a very troublesome unit as well as others. It's design is complicated as all Panasonic products are. I worked on this unit several years ago and the same problem went away. I suspect one of the output transistors in the module has gone rendering the whole thing bad. Whatever happened to a simple transistor replacement. I will keep you informed.

Nov 14, 2008 | Audio & Video Receivers

Not finding what you are looking for?
Pioneer SX-255R Receiver Logo

Related Topics:

130 people viewed this question

Ask a Question

Usually answered in minutes!

Top Pioneer Audio & Video Receivers Experts

Steve Sweetleaf
Steve Sweetleaf

Level 3 Expert

1128 Answers

Ron Dufek
Ron Dufek

Level 3 Expert

398 Answers

gbob59

Level 3 Expert

2963 Answers

Are you a Pioneer Audio and Video Receiver Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...