These are 16 ohm smd maybe with a 2010 footprint. They later DX1000.1 I believe was changed to 2512. Check to make sure the 27 ohm resistor is in value. Sometimes this resistive network around the speaker terminals will burnt out, possible due to a impedance load that exceeds its rating. The amps where designed to be stable @ 1 ohm in 2010 when they where first released. In 2011 they where revised to be 2 ohm stable.
Also, If these resistors continue to burn out after replacing and with no load, there may be cracked capacitors in the feedback loop. They tie back to IC10-TL072, These caps are located at C129,130,229,230- I believe the values are 100nf (0805) and C131,231-3.9nf (0805). If you need to replace them I will check my schematics when I get back to work Monday.
Do you have a scope?Without the 16 ohm and 27 ohm resistors you can check the outputs terminals for oscillation and that will determine if the caps need replacing.
Also, If these resistors continue to burn out after replacing and with no load, there may be cracked capacitors in the feedback loop. They tie back to IC10-TL072, These caps are located at C129,130,229,230- I believe the values are 100nf (0805) and C131,231-3.9nf (0805). If you need to replace them I will check my schematics when I get back to work Monday.
Do you have a scope?Without the 16 ohm and 27 ohm resistors you can check the outputs terminals for oscillation and that will determine if the caps need replacing.
Yes i have a scope..
You are right i just noticed R176 (27 ohm resistor) burbt also..
Another problem im having with this amp is with just power and ground hooked up the amp will power up
Any ideas what might cause this?
You are right i just noticed R176 (27 ohm resistor) burbt also..
Another problem im having with this amp is with just power and ground hooked up the amp will power up
Any ideas what might cause this?
I can walk you through that also,but will have to consult my schematics. Some voltage is leaking through to the remote terminal,maybe through a shorted transistor that switches the DC and audio turn on circuit.
Measure the resistance between the power and remote terminal w/o power applied, and apply power and measure dc voltage between the power ground and remote terminals.
BTW, you can look at the square wave on each channel at the output coils and w/o signal or audio applied you should see a clean 50% duty cycle. The DC voltage should be 1/2 the rail, which I believe has 70 volt dc rail. if there is any jitter or modulation, on one channel or both, must likely the cause is a cracked capacitor/s as I mentioned earlier.The speaker terminals will show only oscillations and of course there should be none w/o signal applied.
If I'm unclear, please ask me to clarify. I have a tendency to omit important info, or get a little bogged down in the details.
Measure the resistance between the power and remote terminal w/o power applied, and apply power and measure dc voltage between the power ground and remote terminals.
BTW, you can look at the square wave on each channel at the output coils and w/o signal or audio applied you should see a clean 50% duty cycle. The DC voltage should be 1/2 the rail, which I believe has 70 volt dc rail. if there is any jitter or modulation, on one channel or both, must likely the cause is a cracked capacitor/s as I mentioned earlier.The speaker terminals will show only oscillations and of course there should be none w/o signal applied.
If I'm unclear, please ask me to clarify. I have a tendency to omit important info, or get a little bogged down in the details.
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Also, if you can post a couple of good quality pics of the board, that will help me determine the model year. Does the chassis have yellow or red pin striping?
The pin stripping is yellow ..
The board says 12-7-2010
I think the caps survived in this amp I get no jitters or anything on the output coils everything looks good..
with just power and ground hooked up i get 12.5 volts on remote terminal..
So i have to order the resistors for this amp ..
Now to figure out what component is defective since the amp powers up with power and ground only
The board says 12-7-2010
I think the caps survived in this amp I get no jitters or anything on the output coils everything looks good..
with just power and ground hooked up i get 12.5 volts on remote terminal..
So i have to order the resistors for this amp ..
Now to figure out what component is defective since the amp powers up with power and ground only
Q10(BCP56) and ZD6(13v) make up a regulated 13v supply for IC12 and the two output drvers IC14 and IC15.
So ZD6 and Q10 is that part of the turn on circuit or is there something else i should check as to why amp powers up with only power and ground hooked up
No, this is not part of the turn on circuit, this supply sets the voltage on IC12, which controls pin 2(CSD) of IC14 & IC15.
The turn on w/o remote issue can be dealt with independentlly. I normally fix the amp so that there is output and then worry about other issues. In other words fixing one problem will not have any effect on the other.
The turn on circuit is comprised of IC19(LM393), Q13 and Q14,both BC807's and a handful of resistors,caps and diodes(1N4148). I would check to see if Q14 is shorted, if so +12V/reg may be passing through the emittor-collector junction to the remote terminal. There may be other reasons why amp turns on w/o remote but this is the most likely
The turn on w/o remote issue can be dealt with independentlly. I normally fix the amp so that there is output and then worry about other issues. In other words fixing one problem will not have any effect on the other.
The turn on circuit is comprised of IC19(LM393), Q13 and Q14,both BC807's and a handful of resistors,caps and diodes(1N4148). I would check to see if Q14 is shorted, if so +12V/reg may be passing through the emittor-collector junction to the remote terminal. There may be other reasons why amp turns on w/o remote but this is the most likely
Thanks for the info greatly appericated..
Do you happen to know the package size of the 16 and 27 ohm resistors?
Do you happen to know the package size of the 16 and 27 ohm resistors?
the 27 ohm should be 1012 and the 16 ohm should be 2010 or 2012. If you will post a picture of the board. The board layout was changed and the sizes on the resistors where stepped up
Ignore the previous post, I checked the BOM for the 2011DX1000.1, and below are the correct sizes.
SMD (1210) 16Ω 5%6R26 R173-174 R25 R273-274SMD (1210) 27Ω 5%1R176
SMD (1210) 16Ω 5%6R26 R173-174 R25 R273-274SMD (1210) 27Ω 5%1R176
I'm gonna replace the smd caps just to be safe since I gotta order parts anyway wondering if the values you listed are correct ?
The parts below in red are the caps you will need.
P300T8F223SMD capacitorC0805 X7R0.022UF 50V 10%4-C129-130 C229-230
P300T8F392SMD capacitorC0805 X7R 3.9nF 50V 10% 2-C231,C131
P300T8F223SMD capacitorC0805 X7R0.022UF 50V 10%4-C129-130 C229-230
P300T8F392SMD capacitorC0805 X7R 3.9nF 50V 10% 2-C231,C131
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Ok replaced the resistors 16 ohm and 27 ohm
Replaced Q10,ZD6, Q13,Q14 C129,C130, C229,C230
Amp has clean output ..
After Replacing Q13,Q14 amp still powers up with only power and ground hooked up..
Any ideas on where to go from here??
Replaced Q10,ZD6, Q13,Q14 C129,C130, C229,C230
Amp has clean output ..
After Replacing Q13,Q14 amp still powers up with only power and ground hooked up..
Any ideas on where to go from here??
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