This one keeps cycling on briefly then straight back off. The power led lights briefly. No other LEDs. None of the large transistors are blown afaik. Found one broken rectifier leg so removed all rects. Ps powers on without rects. New rects in, and amp won’t power -only briefly cycle.
Amp is using sg3825. I was thinking about raising pin 16 to see if the amp will power and hold fir further troubleshooting.
I don’t know if a Clarion SM will match here?
Amp is using sg3825. I was thinking about raising pin 16 to see if the amp will power and hold fir further troubleshooting.
I don’t know if a Clarion SM will match here?
I've found D19 dead shorted and cracked as in a pice missing. Also D21 was checking OK but also looked cracked. R156 blown open (10ohm) which I've replaced.
D19/D21 are pink Zeners with a black stripe, but NO other markings nor numbers. Through hole. Clarion APX1000.2 SM says they're 1n4148.
I'll try powering up amp in a minute.
D19/D21 are pink Zeners with a black stripe, but NO other markings nor numbers. Through hole. Clarion APX1000.2 SM says they're 1n4148.
I'll try powering up amp in a minute.
While I'm sure D19 & R156 were definately needing to be replaced, unfortunately the amp still fails to power up.
The symptom is near exactly the same as this thread, except my amp never stays on where in this thread his amp was able to power on in some cases.
Arc Audio ARC2500-CXL startup issue
This amp powers up for 1/2 second and then powers off. I get a power LED, and also if I turn up the gains and bass boost to mid-full way, the red CLIP led also turns on/off as well.
I lifted r128, r181, r110 and r185, and even replaced U19 to no help.
The symptom is near exactly the same as this thread, except my amp never stays on where in this thread his amp was able to power on in some cases.
Arc Audio ARC2500-CXL startup issue
This amp powers up for 1/2 second and then powers off. I get a power LED, and also if I turn up the gains and bass boost to mid-full way, the red CLIP led also turns on/off as well.
I lifted r128, r181, r110 and r185, and even replaced U19 to no help.
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As mentioned I had already lifted R110/R181/R185/R188 and the amp still would not power up.
The cooling fan works.
Since lifting D23 on accident caused the amp to power and work from all that I can tell, I'm thinking either something within the following boxed area of the schematic has failed, or possibly U12. I'll check through this another time though.
The cooling fan works.
Since lifting D23 on accident caused the amp to power and work from all that I can tell, I'm thinking either something within the following boxed area of the schematic has failed, or possibly U12. I'll check through this another time though.
Attachments
With D23 installed, its a little tough getting some of the measurements on U12. I had to run REC and observe MAX/MIN on my Fluke 16 The MIN numbers are actually when my low current/limiting PS gets pulled down to about 10v as the amp cycles about every 2 seconds.
U12
. MAX | MIN
1. 10.4 | -0.8
2. 9.84 | 6.56
3. 11.86 | 8.36
4. 0
5. 9.89 | 6.56
6. 10.4 | 0
7. 14.4 | 8.4
8. 14.15 | 10
U12
. MAX | MIN
1. 10.4 | -0.8
2. 9.84 | 6.56
3. 11.86 | 8.36
4. 0
5. 9.89 | 6.56
6. 10.4 | 0
7. 14.4 | 8.4
8. 14.15 | 10
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I lifted R153 and made no difference.
Also tried lifting DZ1 - no difference.
I also removed Q29 and Q26 by the fan, and again made no difference.
I'm thinking I might leave D23 out of circuit; mount the amp up and put some higher load tests through it. Maybe something else might crop up then?
Also tried lifting DZ1 - no difference.
I also removed Q29 and Q26 by the fan, and again made no difference.
I'm thinking I might leave D23 out of circuit; mount the amp up and put some higher load tests through it. Maybe something else might crop up then?