Hi,
I need help with my Kicker ZX650.4 amp. On the board it's write KX650.4 VER: 2.1 2003.12.22 and manufacture date 29-12-2005, picture linked. I got the bill of material from Kicker, pdf linked.
For a long time, I have problem with the channel 1 (amp1). Turn off pop noise and sometime he play lower and other time play louder than three others channels.
Recently, the amp stuck in protection mode. It was the faulty transistors on the channel 1, Q112 (tip35c) and Q114 (tip36c) but I replaced the two others on the same pressure bar Q110 (tip41c) and Q114 (tip42c) to have all the same thickness. I found break solders on the RTH5 and two blown resistors R168 and R368. All replaced.
Now the amp works but the intermittent problem/ pop noise still there again. Channel 1 have excessive DC voltage, 1.6v and no resistance (open). All others channels have resistance and no dc offset voltage, less than 0.02v.
Any help will be appreciated
Yoan
I need help with my Kicker ZX650.4 amp. On the board it's write KX650.4 VER: 2.1 2003.12.22 and manufacture date 29-12-2005, picture linked. I got the bill of material from Kicker, pdf linked.
For a long time, I have problem with the channel 1 (amp1). Turn off pop noise and sometime he play lower and other time play louder than three others channels.
Recently, the amp stuck in protection mode. It was the faulty transistors on the channel 1, Q112 (tip35c) and Q114 (tip36c) but I replaced the two others on the same pressure bar Q110 (tip41c) and Q114 (tip42c) to have all the same thickness. I found break solders on the RTH5 and two blown resistors R168 and R368. All replaced.
Now the amp works but the intermittent problem/ pop noise still there again. Channel 1 have excessive DC voltage, 1.6v and no resistance (open). All others channels have resistance and no dc offset voltage, less than 0.02v.
Any help will be appreciated
Yoan
Attachments
I suggest start checking for broken solder pads. Thermal changes fractures solder joints, mainly with lead free soldering. if the amp sometimes works and other times don't, then no damaged components are there. Very rarely a defective component with non firm contact inside one of them.
When running the amp normally but without the cover, flex the pcb and or press it with an isolated piece and or hit it and see if the fault is syncrhonized with such actions.
When running the amp normally but without the cover, flex the pcb and or press it with an isolated piece and or hit it and see if the fault is syncrhonized with such actions.
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Osvaldo makes good suggestions.
Take a good quality picture of the back side of PCB. One overall and two more splitting the board in two photos.
Check the solder on all the jumpers and header socket of Preamp board. It wouldn't hurt to reflow solder on the bigger jumpers and around the output devices.
Take a good quality picture of the back side of PCB. One overall and two more splitting the board in two photos.
Check the solder on all the jumpers and header socket of Preamp board. It wouldn't hurt to reflow solder on the bigger jumpers and around the output devices.
old amps like these with a lot of power usually have tons of bad solder joints. I always resolder the whole board and then start checking for faults and failures 🙂 Most issues are gone this way. If you have a good multimeter check the cement resistors , the ones in white. Sometimes with age they get higher resistance , that causes the power stays within those resistors and not getting to the output.
I attached pictures of the back side of the PBC when I replaced bad resistors. Pictures look worst than it's real.
I followed your advice, I removed cover and pressed on the PBC when amp works. When I gentle press around the header socket (J10), I'm able to get channel 1 works and don't works.
When channel 1 works, he don't have excessice dc voltage and got resistance (continuity).
All three other channels doesn't have changed when I press around the J10 socket. They works fine.
Soon I will disassembly the amp again and take a look to the solders around the header socket (J10) and mainly jumpers.
Thanks Guys, I really appreciate your help. I give you some news soon.
I followed your advice, I removed cover and pressed on the PBC when amp works. When I gentle press around the header socket (J10), I'm able to get channel 1 works and don't works.
When channel 1 works, he don't have excessice dc voltage and got resistance (continuity).
All three other channels doesn't have changed when I press around the J10 socket. They works fine.
Soon I will disassembly the amp again and take a look to the solders around the header socket (J10) and mainly jumpers.
Thanks Guys, I really appreciate your help. I give you some news soon.
Attachments
If you have sufficient time to spent in the rig, look with a manifing glass and give a resolder to all important solderings, say, those with high currents or power relationed. It will prevent a future headache. Use the glass to check that when doing it, don't leave small pieces of solder joining wrong traces that can burn the amp. A knife with thin point will help remvove them and the resin.
I taked time to unplug the amp on the car and disassembly it. I didnt notice any broken solder around the header socket, where I was pressing the pcb and problem going on/off. I don't taked chance and just reflowed a bunch of solders and tracks around the header socket.
The amp play perfectly since two days in my car. Problem solved 🙂
Thanks everyone for the help really appreciate
The amp play perfectly since two days in my car. Problem solved 🙂
Thanks everyone for the help really appreciate
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The amp have play fine a few days but the problem come back with antoher symptom.
Low channel 1, DC voltage, no resitance (open) like before and now he go in protection mode at high volume.
I re-opened the amp and pressed around the header socket a few times. Lot of time when I press, the amp go in protection but sometime the problem gone and he play fine for a few minutes at any volume.
What should I look ? Bad solders again ?
Low channel 1, DC voltage, no resitance (open) like before and now he go in protection mode at high volume.
I re-opened the amp and pressed around the header socket a few times. Lot of time when I press, the amp go in protection but sometime the problem gone and he play fine for a few minutes at any volume.
What should I look ? Bad solders again ?
I think you still have a cold solder joint.
You will need to inspect and reflow solder at header socket and all devices that are mounted around the outputs, including jumpers. The bigger jumpers should be reflowed. Look for rings around solder joints. You may have to remove solder and reflow.
Look for cracked traces, especially around the board mount screws. Check around the mountings for the screws that hold the board in place.
You will need to inspect and reflow solder at header socket and all devices that are mounted around the outputs, including jumpers. The bigger jumpers should be reflowed. Look for rings around solder joints. You may have to remove solder and reflow.
Look for cracked traces, especially around the board mount screws. Check around the mountings for the screws that hold the board in place.
I suggest to remove the posts of the connectors and clean them mechanicaly with fine grane sand paper or the like , and re-put it in its site, replacement with a new connector; or even better, remove it definitivelly and replace it with direct joining using short pieces of wire. This way you will prevent future headaches.