HIFONICS ZXi 1008 car amp has output on one channel only

[stj]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

trace the base input to the power trasistors back.

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Here are a couple of better pictures to aid with the troubleshooting.

[budm]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Can we get straight shot pictures of the whole board top and the bottom side? hard to trace when pictures are in the angle and badly focused.
If you look at your pictures and cannot read the labels or prints on the board, we cannot read them either.

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Hopefully those are a little better if there is specific parts of the board that you want me to take a picture of please let me know. My cell camera is about 4 years old.

Thank you for the help and being understanding with me while I work the bugs with the pictures.

Thank you
Tom S.

[budm]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Well the good thing about the board layout is that the designators for the components are easy to know which one for which channel, for example: R100 for channel 1 amplifier has the same value and use for the same function as R200 for Channel 2 amplifier, so you can at least do the resistance comparison reading between the power amp sections to see if if the bad channel has much difference reading than the good channel, same for the Voltage comparison readings.
Looking at the pictures, I am not if those are dark brown glues being used on the board or not, if they are, they are corrosive (eats up trace and component leads) and conductive.
BTW, what DCV reading do you get at the speaker terminals of each channel?

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

ch 1 -3.5 mv dc
ch2 10.3 mv dc

[budm]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

ch 1 -3.5 mv dc
ch2 10.3 mv dc

If the output or driver devices has leakage or bad then you will have lots more offset Voltage in the Volt range.

[budm]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

BTW, are both line outs OK? if one is dead then the problem is in the pre-amp section.

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

I will check and report back

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Line out on both channels has output so what should I check next?

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Well I did some more checking and testing on this Amp and as far as I can tell everything on the one channel is working perfectly. The other channel has no output, the power transistors are cold to the touch. They are getting the supply rail voltage as far as I can tell. Without a schematic on this amp it is really hard troubleshoot it. Some componet(s) has had to fail to cause the bad channels power transistors no to function at all I just don't know where to start checking. I do get a signal from the op amps but after that I have no clue. If anyone has worked on this model of amp please let me know if there is anything else on it that I can check.

Thanks
Tom S

[budm]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

I have a hard time tracing the board due to the board is double sided (copper traces on both sides of the board).

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Trying to draw up a rough schematic using MultiSim and other programs that I have.

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Amp is now in protect mode. I have removed all of the power transistors on one of the two channels, but it still has the red protect light on. What should I do now?

Thanks
Tom

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Amp is still in protect mode. I have removed the driver transistors, biasing transistors, and output transistors what else do I need to check? All ready verified that I Have 12V going into the transformers of the power supply and it looks like I am getting 12 volts out of it.

In the picture, What does the transistors do that I have highlighted?

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

rectifiers D11, D12, D13, and D14 are removed now along with all of the power and driver transistors and amp is still in protect mode. How would I check for any voltages going into and coming out of power transformers or the power supply section of the amp. Any help in troubleshooting this would be greatly appreciated. By the way this is a class AB amp.

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Desperately need help to troubleshoot the power supply circuit on this amp. It has two transformers in it with each having 2 Primary 2 secondary's on each of the transformers.

How can I just check the transformers themselves for issues?

Thanks
Tom

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

Rectifiers are out amp is out of protect mode. When I try to put any one of the four rectifiers back into the circuit the amp goes into protect mode again. What would cause this and what do I need to check? Rectifiers tested fine so now where do I check?

Any and all help would be greatly appreciated on this.

Thanks
Tom S.

[joshnz]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

is there a fault on the primary of the switching converter?

[tfs2015]

Re: HIFONICS ZXi 1008 car amp has output on one channel only

how would I test for that? Any help would be greatly appreciated.

Thanks
Tom

Wells, MN