T2500-1bdcp no output.

Hi guys working on a T2500-1bdcp had 1 bad power supply fet. I have that clipped out and amp powers on but no output. Checked the class d regulators and was not getting and positive voltage so checked the positive regulator pin 2 and was getting 4 vdc. So I removed the bd card and my class d regulators are getting voltage. Checked for shorts on bd card but didn't find any. Any ideas?
 
Hi guys working on a T2500-1bdcp (board number 1325-55938-03) had 1 bad power supply fet(q1). I have that clipped out and amp powers on but no output. Checked the class d regulators(q2001, q2010, q2012) and was not getting and positive voltage so checked the positive regulator (u1000) pin 2 and was getting 4 vdc. So I removed the bd card (1325-55947-02) and my class d regulators are getting voltage. Checked for shorts on bd card but didn't find any. Any ideas
 
This amp may not use R9. At some point, they moved the source for the SMD regulators to U1000.

Did you see one of the SMD regulator transistors heating more than the others when the class D driver board was in the circuit?

An IR thermometer may work if you can get a clear shot to the ICs on the driver board.

Does this amp have the CP driver board or the single driver board?
 
This amp may not use R9. At some point, they moved the source for the SMD regulators to U1000. ( I do have an r9 on the bd card)

Did you see one of the SMD regulator transistors heating more than the others when the class D driver board was in the circuit? ( I didn't notice)

An IR thermometer may work if you can get a clear shot to the ICs on the driver board.( I have the bd card out and separated and am making jumpers to run out of amp)

Does this amp have the CP driver board or the single driver board? (This one has the cp grandaughter board)
 
R9 was a large resistor on the main board. If you read 0 ohms between U1000 and the center terminals of the SMD regulator transistors, this amp doesn't use the R9 I was referring to.

The canned air (dispensed with the can inverted) may be the easiest solution. If the driver board has a problem that's dragging the voltage down, freezing them with the liquid canned air and watching to see if one defrosts very quickly may be the easiest way to find the defective component.
 
I ran the amp for 5 minutes.
On the main board.
T2001 170*f. hotter by 20*f then t2000
Q2001 was at 160*f
Q2012 was 130*f
Q2000,q2010 was 95*f
On the bd card
U4 was 80*f
Q24 was 80*f
Every thing else was 73*f
On bd card grandaughter board
Q10 80*f
Everything else was 73*f.
 
Pin2 of u2000 an u2002 for the first 10 seconds of amp powered on
 

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