Hello everyone I am looking for some help if anyone could help me fix my Pioneer VSX-D514 amp.
It was working fine up to now and last week when switching it on the relays started oscillating meaning clicking on and off continuously until the unit switched off completely and would not turn on.
After a lot of turn on and turn off attempts it switched on. I checked the output there was only 2 mv DC offset and it stayed on without saying AMP ERROR or DC OFFSET. All normal
Tuned it off opened it, turned on, did the Advanced surround + Enter keypress and noticed the clicking relay was from the Main AC board. After that it would not turn on at all i.e. the relay on the main AC board is not longer working
I checked the voltages based on the service manual there is a proper +5V standby and i am getting 3.3V from the AC WK signal. Traced the AC signal path there is no blown fuse. Did also a check on the amp protection lines DC DET and overload lines are at zero volt. There is proper voltage at the relay pins but the relay driver transistor base is at zero volts.
Is there anything else anyone might suggest me to check? Thanks
It was working fine up to now and last week when switching it on the relays started oscillating meaning clicking on and off continuously until the unit switched off completely and would not turn on.
After a lot of turn on and turn off attempts it switched on. I checked the output there was only 2 mv DC offset and it stayed on without saying AMP ERROR or DC OFFSET. All normal
Tuned it off opened it, turned on, did the Advanced surround + Enter keypress and noticed the clicking relay was from the Main AC board. After that it would not turn on at all i.e. the relay on the main AC board is not longer working
I checked the voltages based on the service manual there is a proper +5V standby and i am getting 3.3V from the AC WK signal. Traced the AC signal path there is no blown fuse. Did also a check on the amp protection lines DC DET and overload lines are at zero volt. There is proper voltage at the relay pins but the relay driver transistor base is at zero volts.
Is there anything else anyone might suggest me to check? Thanks
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Check the capacitors on that stand-by board, you might have one that’s leaking and won’t hold the relay voltage needed turn stay latched.
in the schematic page 29/91.
check the resistors R751, R752, R755, R761, R762,
they should be 0V or a few mV to ground,
if there is voltages there, power IC might be in trouble and the protection relay won't click.
in page 30/91,
check all the voltages in the power supply .
check the resistors R751, R752, R755, R761, R762,
they should be 0V or a few mV to ground,
if there is voltages there, power IC might be in trouble and the protection relay won't click.
in page 30/91,
check all the voltages in the power supply .
Thank you bullit and Alex I will do the checks that you mentioned and revert back. I will also do another test which will be to disconnect the board and apply 12v to the relay switching transistor relay and transistor emitter and apply a 0.7 to 1v base voltage to see if the relay circuit operates properly. I will update back the post
Hello I did the checks that you mentioned currently there is no voltage on any section of page 30/91and there is no voltage on resistors r751 r752 r755 r761 r762. I checked the caps on the standby board by de soldering one lead and checking with a capacitance meter there is no issue.
What I did observe is that Q51 has close to 0v base voltage and as such RY51 is not switched on. RY51 is what powers on the main transformer which in turn supplies all the voltages for the unit to run. TR1on page 31is operating providing 5v 3.3v and 12v to the relay. Do you think there is anything more I could check? Thank you
What I did observe is that Q51 has close to 0v base voltage and as such RY51 is not switched on. RY51 is what powers on the main transformer which in turn supplies all the voltages for the unit to run. TR1on page 31is operating providing 5v 3.3v and 12v to the relay. Do you think there is anything more I could check? Thank you
Sorry I mistook your description.
on page 31, the AC part,
the regulator 78M56 voltage, Input 12v, Output 5.6v, correct?
as you mentioned, is the joint of R53, R54 provide 3.3v?
if 5.6v present.
if the Base of Q51 no voltage appear when you switch on,
it is the Q51 that received no turn on signal from the c p u.
page 23,
IC 9001, Main u-COM PD5963A,
check if all the 5v supply is normal.
check pin 58,
see if turn on signal voltage appear when you switch on at the front panel.
on page 31, the AC part,
the regulator 78M56 voltage, Input 12v, Output 5.6v, correct?
as you mentioned, is the joint of R53, R54 provide 3.3v?
if 5.6v present.
if the Base of Q51 no voltage appear when you switch on,
it is the Q51 that received no turn on signal from the c p u.
page 23,
IC 9001, Main u-COM PD5963A,
check if all the 5v supply is normal.
check pin 58,
see if turn on signal voltage appear when you switch on at the front panel.
Hi zeus_threat,
Check the volt IC51 out = 5.6v and R53 point (AC WUP) it should be 5v. if not get check or remove/replace D58. check IC9001 PIN 18 (5V) replace/remove C9015
Regards
MANOJ
Check the volt IC51 out = 5.6v and R53 point (AC WUP) it should be 5v. if not get check or remove/replace D58. check IC9001 PIN 18 (5V) replace/remove C9015
Regards
MANOJ
Hi Manoj I think your suggestion could be on the right track. Right now my acwkup is 3.3v and I will look closer at D58. Ic58 which is an njm7805 is giving me 5.3v I need to check with another multimeter. I will also check ic9001. Thanks for the advice
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Hello I did some test yesterday as follows:
Disconnected the cable CNJ57 and measured acwu I got only 1.9v
Checked D55 and D58 with component tester all OK.
Checked R53 and R54 both measure 3.3k and 10k
Tried replacing D55 with an 1n4007 and D58 with a 5.1 v zener. Tested no turn on checked voltages 3.3v
Removed R54 and placed a 1uf non polar cap voltage boosted to 4.43v DC at D58. Tested no turn on
I have identified C9015 on the board I will check it next.
In case anyone has any advice most welcome. Thank you
Disconnected the cable CNJ57 and measured acwu I got only 1.9v
Checked D55 and D58 with component tester all OK.
Checked R53 and R54 both measure 3.3k and 10k
Tried replacing D55 with an 1n4007 and D58 with a 5.1 v zener. Tested no turn on checked voltages 3.3v
Removed R54 and placed a 1uf non polar cap voltage boosted to 4.43v DC at D58. Tested no turn on
I have identified C9015 on the board I will check it next.
In case anyone has any advice most welcome. Thank you
Sorry for the late update but I managed to check c9015 it's measuring 1nF as expected. I will try to look into the VFD display board as it's the oone that sends the signal to the main uCom to switch the main power relay when the power switch is pressed. I will also check the power button board it seems to be working through an ADC I will check if the necessary voltages are present