How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Louie Your Own Question
Louie, Technician
Category: Home Theater-Stereo
Satisfied Customers: 1218
Experience:  Have been in the business 25+ yrs., down to component level.
Type Your Home Theater-Stereo Question Here...
Louie is online now
A new question is answered every 9 seconds

My system will not turn on but it does have a red light on.

Customer Question

Hi my system will not turn on but it does have a red light on. Sorry if my internet drops out.
JA: What's the make and model of your tv, and has turning it on been a problem in the past?
Customer: RX-V471 it used to work fine but it just stopped day, the unit has only been used about 3 times.
JA: What happened right before this popped up? What troubleshooting have you tried?
Customer: We plugged a USB into it
JA: Anything else you want the theater expert to know before I connect you?
Customer: No I think thats all, I just dont want to throw it out when it has only been used a few times and it cost quite alot of money.
Submitted: 3 months ago.
Category: Home Theater-Stereo
Expert:  Louie replied 3 months ago.

Hi and welcome to JustAnswer, I’m Louie. Sorry you had to wait awhile but I’ll do my best to help.
Initially, have you tried unplugging for an extended period of time? ...and hour...hours?

And then plug back in but into a different outlet? ...with no speaker wires connected?

Customer: replied 3 months ago.
We used to have a Panasonic TV and it worked fine then one day my son plugged his iPod into the USB outlet and it stopped working. We tried with the speakers connected and without them but all we get is the red light.
Expert:  Louie replied 3 months ago.

Please consider / try unplugging as above described.

Customer: replied 3 months ago.
I have tried plugging it into several points
Expert:  Louie replied 3 months ago.

Then it would be indicative of an internal hardware issue.

Are you then considering a DIY (do-it-yourself) repair approach? If yes, do you have access to and familiar with a multi-meter and even a soldering iron?

Customer: replied 3 months ago.
I will try myself and yes I am able to use a soldering iron and a multimeter.
Expert:  Louie replied 3 months ago.

Great on the DIY!
Please post back with clear pictures of the internal circuitry. Click HERE.

These pictures would then serve as common references.

Customer: replied 3 months ago.
What should I be looking for etc
Expert:  Louie replied 3 months ago.

Please see above post.

Customer: replied 3 months ago.
I'm trying to send you photos. Which board do u need?
Customer: replied 3 months ago.
Do you need any other photos?
Customer: replied 3 months ago.
Are u still there?
Expert:  Louie replied 3 months ago.

Thank you for allowing me time to read your post, reference the Service Manual/schematic diagrams and compose this reply.

Let's start with the standby power supply board. This would be the upright squarish board towards the rear left with the front facing you.

Still, let's try check and review the basics. Proposed preliminary tries (if have not been done):

  • • +5.5V @ connector CB376;
  • • +2.7V & +0.8 before & after resistor R3722 when attempting to turn ON;
  • • +3.4V @ collector of Q3703;
  • • +3.3V @ junction of resistors R3724 & R3725;
  • • +3.3V @ cathode of D3709.

A friendly reminder: voltage measurements by its very nature requires that the unit be plugged in and turned on. It is therefore LIVE! Please exercise due care and caution.

Customer: replied 3 months ago.
Hi I'm having some trouble with my multi meter
Customer: replied 3 months ago.
My brain isn't working too well at the moment so do I have it on the right settings
Expert:  Louie replied 3 months ago.

It should be set to DC Volts; ---

Customer: replied 3 months ago.
Just noticed that the button that turns the unit off is not responding?
Expert:  Louie replied 3 months ago.

The front panel top left POWER button?

Customer: replied 3 months ago.
Expert:  Louie replied 3 months ago.

This model would always be on standby condition as long as plugged into an outlet.

Customer: replied 3 months ago.
Oh ok
Expert:  Louie replied 3 months ago.

The voltage checks when able please; TNX

Customer: replied 3 months ago.
Sorry for the delay won't be long
Expert:  Louie replied 3 months ago.

No prob; when able.

Customer: replied 3 months ago.
CB 376 1.5
R3725 2.5
R3733 2.2- 0.9
Q3703. 3.4
D3709 4.2
Expert:  Louie replied 3 months ago.

The "...CB 376 1.5..." is rather low as it should read +5.5. Please re-confirm. 2 pins of CB376 should have this +5.5V

Carefully read voltage between the 2 pins of capacitors C3714 and C3715.