Dynex DX-L40-10A Won't turn on.

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

Here's the pics that I took.

Here's the results of trying the resistors.
GND 0
GND 0
STB 5.3
5V S 9.8
5V S 9.8
12V 0
12V 0
GND 0
BR1 0
SW 0
GND 0
GND 0
5V_M 0
5V_M 0

[budm]

Re: Dynex DX-L40-10A Won't turn on.

Here's the pics that I took.

Here's the results of trying the resistors.
GND 0
GND 0
STB 5.3
5V S 9.8
5V S 9.8
12V 0
12V 0
GND 0
BR1 0
SW 0
GND 0
GND 0
5V_M 0
5V_M 0

You should verify your meter and meter batteries, 9.8VDC on the 5Vstandby is not right.
Notes: STB pin = PS_ON

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

I will double check when I get home.

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

I checked my tester by checking the voltage in the wall outlet and that came out to be 123v. Tested a couple AAA & AA batteries and they were in the range of 1.3v to 1.5v.

Is there a better way to check?

[budm]

Re: Dynex DX-L40-10A Won't turn on.

So the meter is set to DCV when you check the Voltages on the connector? What did you use for the GND ref point?

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

I used one of the metal rails and yes it's set to DCV.

I did some checking of my meter and it was out of calibration. I have no sure way of confirming its accuracy but I adjusted it so that it's reading 110v AC with the wall outlet. I will recheck the readings sometime today. I still have to finish shoveling but with this kinda cold it requires some rewarming.

[budm]

Re: Dynex DX-L40-10A Won't turn on.

There should be calibration for the DCV also.
To have 9.8V instead of 5V feeding the logic circuits, lots of parts would have been damaged.

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

I feel stupid because I did have my meter in VAC. Here's the new results. I don't think my meter it quite calibrated correctly yet but I'm sure it's better than it was.

GND 0
GND 0
STB 2.48
5V S 4.28
5V S 4.28
12V slow drop to 0.01
12V slow drop to 0.01
GND 0
BR1 slow drop to 0.01
SW slow drop to 0.01
GND 0
GND 0
5V_M slow drop to 0.01
5V_M slow drop to 0.01

I found some readings on the main board but I'm thinking there's a cap that might be bad in there.

[budm]

Re: Dynex DX-L40-10A Won't turn on.

I used one of the metal rails and yes it's set to DCV.

I did some checking of my meter and it was out of calibration. I have no sure way of confirming its accuracy but I adjusted it so that it's reading 110v AC with the wall outlet. I will recheck the readings sometime today. I still have to finish shoveling but with this kinda cold it requires some rewarming.

Since you made the adjustment to the meter so now it is no longer correct. I would get another meter first since wrong reading will cause lots of wrong diagnostic of the problems.
4.28V for 5VSTBY is too low for the circuit to function properly, but since we do not know if the your meter is correct or not at this point it will not be good to go further until you have good meter.

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

Since you made the adjustment to the meter so now it is no longer correct. I would get another meter first since wrong reading will cause lots of wrong diagnostic of the problems.
4.28V for 5VSTBY is too low for the circuit to function properly, but since we do not know if the your meter is correct or not at this point it will not be good to go further until you have good meter.

The meter itself is pretty new and it was a cheap one from Harbor Freight. It probably needed calibration right out of the box anyways since it was a cheap one. I'll take it to work and have one of our electricians check it for me. I'm sure they have a reliable voltage source to fine tune my meter with.

[budm]

Re: Dynex DX-L40-10A Won't turn on.

Since you adjusted the meter to make it reads 110VAC instead of leaving it at 123V that it shows before, so the meter is now showing low readings.
US has not been using 110VAC for a long time, it has gone up from 110 to 115 to 117, and now to 120VAC.

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

I recalibrated my meter with a known good one and here's the results.

GND 0
GND 0
STB 2.8
5V S 4.84
5V S 4.84
12V slow drop to 0.01
12V slow drop to 0.01
GND 0
BR1 slow drop to 0.01
SW slow drop to 0.01
GND 0
GND 0
5V_M slow drop to 0.01
5V_M slow drop to 0.01

[CapLeaker]

Re: Dynex DX-L40-10A Won't turn on.

Hmm... It's like the power supply turns itself off. 5V STBY going out, PSon coming back, tries to fire up, but then shuts down. Dang. This test is done with the main board installed, no resistors?

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

Correct. Boards in and connected, no resistor.

[CapLeaker]

Re: Dynex DX-L40-10A Won't turn on.

O.k. in post 32 you say for example: 5V_M slow drop to 0.01
What is the highest voltage reached on the 12v and 5v m?
Can you leave the board in, unplug the main board and force it on again? Redo all the measurments?

Maybe heat has something to do with it?

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

I'll try that tonight. I do know that the voltage starts dropping immediately after plugging in.

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

Plans changed for tonight. Gonna try again tomorrow.

[Funda]

Re: Dynex DX-L40-10A Won't turn on.

Should I be trying to unscrew the main board and take readings while its powered up from underneath?

[CapLeaker]

Re: Dynex DX-L40-10A Won't turn on.

If you want you can always solder some wire on these hard to get at places. Just remember to be carful with these open wires, you may not want them to short out on something.

[splitcrete]

Re: Dynex DX-L40-10A Won't turn on.

Did you try to heat up the main board where I circled in red. There is a bad cap there. Just pin point it. Good practice.