I got this amplifier and the power supply section was blown. So I replaced the mosfets, resistors and driver IC’s. I checked the outputs for shorts and they all test fine. I powered up the amp and it tried to come on then the blue and red light came on. I checked the capacitor between the speaker terminals and it’s within spec. I tried removing the output driver IC’s and still doesn’t come on. What does the blue and red light mean? I know blue means on and red means procreation but what does it mean when they both are on?
Solid red LED means short circuit or speaker impedance too low.
With the power on wiggle and twist the output inductor to see if anything changes. Check for components heating up. Check the surface mounted resistors around the output transistors.
Check the surface mounted diodes around the output transistors. You may have to remove them from the circuit to get a good reading on them.
With the power on wiggle and twist the output inductor to see if anything changes. Check for components heating up. Check the surface mounted resistors around the output transistors.
Check the surface mounted diodes around the output transistors. You may have to remove them from the circuit to get a good reading on them.
Then you’ll have to check the voltages on the pins of the PIC16 programable IC that they use. Use a DMM in DC voltage mode. Black probe on the negative power terminal.
Check the voltages on all the pins, staying away from pins 2 and 3 that are connected to the oscillation crystal. If you probe those pins you may damage the power supply.
If you have Perry’s guide to amplifier repair you can look up the info you need under Generic Class D Type 5. If you don’t have his guide then post the voltages that you get.
Check the voltages on all the pins, staying away from pins 2 and 3 that are connected to the oscillation crystal. If you probe those pins you may damage the power supply.
If you have Perry’s guide to amplifier repair you can look up the info you need under Generic Class D Type 5. If you don’t have his guide then post the voltages that you get.
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Did you check the SMD resistors (1k ohm) and the SMD caps (68nf) around the gate driver ICs in the power supply? I find that sometimes those resistors will be out of tolerance depending on how hard the power supply went down. Particularly the 1k ohm resistors around the driver IC and sometimes they have a couple of them amongst the gate resistors. There will be one 1k ohm resistor per bank of 4 mosfets. You’ll see two resistors close together in the line of gate resistors. One will be like 10 ohm and the other one will be 1k ohm.
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