This is my first post on this site have gotten lots of great info in the past on here. Today i got a kicker 06zx700.5 that had a non working sub channel. amp would power up green and play on the 4 channel side. so i took it apart found one of the subwoofer side power supply fet blown along with the 100ohm resistor replaced with new irf 3205. before i did that i checked all resistors and gate supply voltage everything was good. now with the parts replaced amp goes into protect checked all ouputs and output resistors and everything is ok. but i did notice if i removed the card (pas315-02) that it would power up green and stay that way but once i plug it back in it goes right back into protect and kinda goes in and out of protect every 4-5 seconds. im not a pro at this stuff but i have repaired 40+ amps in the past with success and never had problems after that but kicker amps get me every time hoping someone could help me please and thank you.
There is an inductor between that driver board and the preamp board. Do you see a pulse of DC on either terminal of that inductor as the amp tries to power up (driver board in the circuit)?
yes a very quick pulse when the amp is trying to power up it actually goes red to green about every 2 seconds
With the black probe in the 2g pin of the driver board and the red probe alternately on pins 9 and 11 of the LM361, do both pins swing positive, negative or one positive while the other swings negative as it tries to power up?
i also just noticed it will even power up green and relay will kick in when i have the driver board in and remove the bigger board with the rca inputs and pots
its really quick when it happen but pin 9 goes negative and pin 11 seems to go negative also but when i remove the bigger board by the way is (pas403-01) pin 9 has negative voltage and pin 11 has positive voltage
On the driver board, do you see significant DC on the S-in (black probe on 2gnd) with the preamp board in place and no DC without the preamp board?
with the board in its goes from bout .5 dc to .9 while the amp is trying to power up
and with the board out it stays around .5
and with the board out it stays around .5
Check the DC voltage on all output pins of all of the op-amps on the preamp board. Do any have more than a fraction of a volt of DC? Place the black meter probe on one of the non-bridging speaker terminals or on one of the a-ground pins.
If the amp won't stay on, remove the driver board.
If the amp won't stay on, remove the driver board.
u105
pin 1 = 0.00
pin 7 = -3.5
u102
pin 1= -4.8
pin 7= 0.00
u103
pin 1= -5.4
pin 7= -5.5
u101 TL074c
pin 1= .003
pin7= .002
pin8= it keeps showing .OL im using a fluke 73 series 2
pin14= also showing .OL
pin 1 = 0.00
pin 7 = -3.5
u102
pin 1= -4.8
pin 7= 0.00
u103
pin 1= -5.4
pin 7= -5.5
u101 TL074c
pin 1= .003
pin7= .002
pin8= it keeps showing .OL im using a fluke 73 series 2
pin14= also showing .OL
actually i had pushed my range button by accident on pin 8 on the TL074c im getting -6.5 and on pin 14 i get -10.6
Confirm that all of these have both positive and negative supply voltage on their power supply pins.
Of all of the op-amp sections that have offset, which of those have the inputs (inverting and non-inverting) to those sections that don't match VERY closely in voltage?
Are any of the op-amps with DC hotter than others with the same part number?
Are any of the op-amps with DC hotter than others with the same part number?
u102 is slighly warmer than the rest and 2in+ and 2in- on that one are not matching like the rest of the op amps if im doin what you are saying right get kinda confused with all this
Check to see if the leg on one of the potentiometers is shorting to a feedthrough (in circle) are shorted.
Solder a bridge between the non-inverting input pin and the output pin of that channel of that op-amp. Does the make the voltage on the two inputs match? If not, the op-amp is likely defective.
Solder a bridge between the non-inverting input pin and the output pin of that channel of that op-amp. Does the make the voltage on the two inputs match? If not, the op-amp is likely defective.
Attachments
i figured out that u102 was defective i replaced it and the amp powered up but then i noticed that when i move the sub bass pot it makes the speaker pop real hard and the amp goes to protect and the pot is feeling very loose and the traces from there lead back to the u102 so im guessing i need to replace that pot
when the amp is powered up and i have the speaker hooked up to the sub output and the rca's hooked up to my phone once i put the music on play the sub pops real loud and amp goes to protect even with my phone volume on 1 and the gains turned all the way down on the amp it doesnt make a difference at all jus the slightest little signal goin to the amp and it does it
also do you have any idea where i can get them pots from any or numbers for them so i can find some
Mouser may have a sub but the problem with pots like this is they don't all have the same pin configuration. It may be repairable.