i wantit iph10011

[Jahson]

I have a problem with this iphone docking device, its got a intermittent fault, as some times it will power up and sometimes it wouldn't (switch on or wouldn't switch on).

Ive open the unit had a look inside did a few checks on the caps with a ESR meter all seems to be ok.

Can hear I slight ticking sound I do think its coming from the power supply side of the boards.

Don't know if I have done this correctly but I sprayed a few IC's with some freeze spray im I right in thing the one that heats up rapid is the faulty component.

Anyhow I think I have detected a faulty ic based on the above method screwed on to a heatshield, component Q1=SVD10N60F.

I removed this compenent to test

N - P probes
1 - 2 = ol
1 - 3 = ol
2 - 3 = 0.509

P - N probes
1 - 2 = ol
1 - 3 = ol
2 - 3 = 0.068 or sometimes ol

Is this correct my method of testing

Power Board=QFD-PQ262507

Ive seen similar component on fleabay I understand once its got (10N60F) should it be ok?
Can provide photo's if needed.

[stj]

Re: i wantit iph10011

that's a fet,
if it has an internal diode then your readings look like it's o.k.

got any foto's?

[Jahson]

Re: i wantit iph10011

will do

[Jahson]

Re: i wantit iph10011

Sorry for delay photos added.

Also what ive noticed when you power off the unit, just before the unit turns off like 2-3 seconds the control panel lights up then off again, the 18 volts is present.

Ticking sounds like its coming from the transformer (don't believe this is the problem thought.

[stj]

Re: i wantit iph10011

maybe a short someplace.

did you try it without the output cable connected?
if you did and it still wont work, check the diodes - including the ones bolted to the heatsink.

the other thing you could try is replace the 2 small caps in the center section - one of them is the startup cap.

[Jahson]

Re: i wantit iph10011

Sorry had internet connection problems yesterday, I have tested all caps, those that I wasn't to sure on the readings I removed & tested.

In the center of the board infront of that Q1 IC and between the transformer that diode looking thing on the board it says (BL1) that is reading short but do not know what it is, I have not removed it from the board to test.

Do need a photo of the underneath of the board?

[Jahson]

Re: i wantit iph10011

Yea I did replace one those caps in the center as you can see, all others are gold/black.

On the board when its working im getting 20.20v on those outputs should be (18v)

When you turn system on and its not working you can see the voltage been drained away slowly.

Those diodes I will remove and report readings.

[chozo4]

Re: i wantit iph10011

If it switches on and works fine but at times it won't switch on at all. Have you checked all the solder joints for a loose component lead? If the intermittence is also based on if you tap it a bit and it then works that could confirm a possible bad solder joint as well.

The slight ticking you also mention sounds like one of the mosfets aren't kicking on. I would also double check the joints on them as well since you've double checked all the caps. Would it be possible to get a good closeup of the underside of the board?

[Jahson]

Re: i wantit iph10011

Recapped with new low esr caps still ticking, im going pull the 3 diodes on the heat shield well 2 connected to the heat shield.

The 4 caps I pull were 1000uf 25v reading = 938uf on average.
The 2 caps 1000uf 16v reading = 927uf-932uf.

So all those 6 caps have been replaced.

Yea I post photos of underneath, I have looked for dry joints & touched up anything looking suspect.

As I said before the same thing happens, the buttons flash a few seconds before it actually turns off, then you get like a working state for 1-2 seconds the 18v, then it switches off.

I pull those 3 diodes & report findings. Cheers

All the funny soldering rework is by me, you may find it hard to tell it apart

[Jahson]

Re: i wantit iph10011

Diode 7 - (SR10100CTF-1F13)

P - N = probes
1 - 2 = 0.259, with meter now set too ohms 1.1 & rising
3 - 2 = 0.258, with meter now set too ohms 1.1 & rising
1 - 3 = ol , with meter now set too ohms varies ranges

N - P = probes
1 - 2 = ol , with meter now set too ohms varies ranges
3 - 2 = ol , with meter now set too ohms varies ranges
1 - 3 = ol , with meter now set too ohms varies ranges

Also with meter set to bleeper mode everything reads ok as no bleeping to indicate a short.

[Jahson]

Re: i wantit iph10011

Diode 8 & 9 (MBR10150FCT-1B01)

This reading from (Diode 9)

P - N = probes
1 - 2 = 0.288, with meter now set too ohms 1.3 & rising
3 - 2 = 0.287, with meter now set too ohms 1.3 & rising
1 - 3 = ol , with meter now set too ohms 20.2 & rising

N - P = probes
1 - 2 = ol , with meter now set too ohms 18.0 & dropping
3 - 2 = ol , with meter now set too ohms 18.0 & dropping
1 - 3 = ol , with meter now set too ohms 22.0 & drop then rising

Also with meter set to bleeper mode everything reads ok as no bleeping to indicate a short.

This reading from (Diode 8)

P - N = probes
1 - 2 = 0.268, with meter now set too ohms 1.2 & rising
3 - 2 = 0.271, with meter now set too ohms 1.2 & rising
1 - 3 = ol , with meter now set too ohms 0.7 & rising

N - P = probes
1 - 2 = ol , with meter now set too ohms 07. & rising
3 - 2 = ol , with meter now set too ohms 08. & rising
1 - 3 = ol , with meter now set too ohms 07. & rising

Also with meter set to bleeper mode everything reads ok as no bleeping to indicate a short.

Hope these reading you can make sense off?

[chozo4]

Re: i wantit iph10011

Maybe it's how the light is reflecting off the joints but the solder joints just above R19 on the bottom of the board look questionable.

[Jahson]

Re: i wantit iph10011

I do see what your saying, will recheck.
Does those readings look questionable, specially that diode 9

Theirs 2 IC's that I need to check off board located 6 o'clock & 7-8 o'clock ish off the transformer.

[stj]

Re: i wantit iph10011

the diode readings look strange, does your meter have a diode-test?
probably not i suppose or you would have used it.

[Jahson]

Re: i wantit iph10011

Yea the first set of readings are in diode mode. if you read the post you could of tell. I am not here to be smart & witty I am looking help.

Diode 8 & 9 (MBR10150FCT-1B01)

This reading from (Diode 9)

P - N = probes
1 - 2 = 0.288 diode mode, with meter now set too ohms 1.3 & rising
3 - 2 = 0.287 diode mode, with meter now set too ohms 1.3 & rising
1 - 3 = ol diode mode, with meter now set too ohms 20.2 & rising

N - P = probes
1 - 2 = ol diode mode, with meter now set too ohms 18.0 & dropping
3 - 2 = ol diode mode, with meter now set too ohms 18.0 & dropping
1 - 3 = ol diode mode, with meter now set too ohms 22.0 & drop then rising

Also with meter set to bleeper mode everything reads ok as no bleeping to indicate a short.

This reading from (Diode 8)

P - N = probes
1 - 2 = 0.268 diode mode, with meter now set too ohms 1.2 & rising
3 - 2 = 0.271 diode mode, with meter now set too ohms 1.2 & rising
1 - 3 = ol diode mode, with meter now set too ohms 0.7 & rising

N - P = probes
1 - 2 = ol diode mode, with meter now set too ohms 07. & rising
3 - 2 = ol diode mode, with meter now set too ohms 08. & rising
1 - 3 = ol diode mode, with meter now set too ohms 07. & rising

Also with meter set to bleeper mode everything reads ok as no bleeping to indicate a short.

Hope these reading you can make sense off?

[stj]

Re: i wantit iph10011

that's o.k.

[Jahson]

Re: i wantit iph10011

Anything else I could try