Photos are at http://www.tapsupply.co.uk/CVR4/m2atx1.jpg and http://www.tapsupply.co.uk/CVR4/m2atx2.jpg

Resistance readings after shorting all caps...

Pin no. - Older mobo - Newer mobo

Pin1:- 1217 - 1009
Pin2:- 1217 - 1009
Pin3:- 001 - 001
Pin4:- 1 - 1
Pin5:- 001 - 001
Pin6:- 1 - 1
Pin7:- 001 - 001
Pin8:- 1 - 1
Pin9:- 15 - 20
Pin10:- 1 - 1
Pin11:- 1 - 1
Pin12:- 1 - 1

Pin13:- 1217 - 1010
Pin14:- 1 - 1
Pin15:- 001 - 001
Pin16:- 1 - 1
Pin17:- 001 - 000
Pin18:- 001 - 001
Pin19:- 001 - 000
Pin20:- 1 - 1
Pin21:- 1 - 1
Pin22:- 1 - 1
Pin23:- 1 - 1
Pin24:- 001 - 001

 

hey I need to see the connector to the mobo, and also pugged in

the readings are in ohms or what ...please be specific
how u labeling the Pin numbering

 

Sorry R!f@@..

Photos are at http://www.tapsupply.co.uk/CVR4/m2atx3.jpg and http://www.tapsupply.co.uk/CVR4/m2atx4.jpg

 

even though it is not a problem for some occasions, using 20 pin supply in a 24pin board is not recommended. I am checking the u'r resistance readings and I'll tell u later about the extra 4 pins

 

U missed the 4 pin connector near the processor

 

Photos are at http://www.tapsupply.co.uk/CVR4/m2atx1.jpg and http://www.tapsupply.co.uk/CVR4/m2atx2.jpg

Resistance readings after shorting all caps...

Pin no. - Older mobo - Newer mobo

Pin1:- 1217 - 1009
Pin2:- 1217 - 1009
Pin3:- 001 - 001
Pin4:- 1 - 1
Pin5:- 001 - 001
Pin6:- 1 - 1
Pin7:- 001 - 001
Pin8:- 1 - 1
Pin9:- 15 - 20
Pin10:- 1 - 1
Pin11:- 1 - 1
Pin12:- 1 - 1

Pin13:- 1217 - 1010
Pin14:- 1 - 1
Pin15:- 001 - 001
Pin16:- 1 - 1
Pin17:- 001 - 000
Pin18:- 001 - 001
Pin19:- 001 - 000
Pin20:- 1 - 1
Pin21:- 1 - 1
Pin22:- 1 - 1
Pin23:- 1 - 1
Pin24:- 001 - 001

u have a serious problem buddy

 

Power up the car PSU without the board and measure the voltages

Put a jumper between the green wire (pin 16 or PSU ON) and pin 17, black.
When shorted the psu should switch on. give me voltages

 

Ok, on both boards the 4 pin connectors measure 0 ohms on the negative sides and infinity on the 12v sockets.

On to the car PSU - all orange measure 3.28v, yellow 11.88v, red 5.0v, purple 5.0v, green 0v, blue -12.00v and grey 5.01v

The pinout readings for the resistances are in the same order as the earlier diode readings.

 

R!f@@ - hang on!

Upped the setting on the DMM to 20k and re-tested one of the boards...

In the same pin order

1 - 1.25
2 - 1.25
3 - 0
4 - 2.29
5 - 0
6 - 2.29
7 - 0
8 - INF
9 - 0.02
10 - 17.8
11 - 17.8
12 - INF

13 - 1.25
14 - INF
15 - 0
16 - 4.84
17 - 0
18 - 0
19 - 0
20 - INF
21 - 2.29
22 - 2.29
23 - 2.29
24 - 0

On the 4-pin, yellow reads at 59.3k on both and 0k on black

 

I also get the same infinite readings on the other board

 

Ok, on both boards the 4 pin connectors measure 0 ohms on the negative sides and infinity on the 12v sockets.

Hmmmmmmm! PSU OK ...right?

On the 4-pin, yellow reads at 59.3k on both and 0k on black

this tells you that VRM regulator is not the culprit this is good

 

OK here goes..
see that pin no. 9 is showing a 0 resistance..right
this pin switches on the supply once the power button is pressed.
so it should not show low resistance, this pin is an open collector transistor which shorts to ground to power on.
Double check the PSU_ON pin and if low resistance is shown, trace that pin to the transistor.
post back

 

I'm sooooooooooo happy today.
drinks on me guys... Enjoy

 

Did you finish your project by any chance???

 

R!f@@ - double-checked the zero resistance readings on pin 9...

Sorry but having set my DMM to 200ohm range I now get a reading of 15 for this pin on the old board and 19ohms on the newer one.


D'oh!

 

That's a problem. Trace that pin to the transistor which grounds that terminal.
It will be a surface mount. You can just test for low continuity reading in the diode check range. the CE terminals should not give a low reading, it will give an open or sometimes 1V o more. Do a BC, BE and a CE check. If found faulty, try to desolder it without damage to the board or the transistor. And check the transistor and also the solder pads of the board for shorts, you can try this with the two boards.
Post back soon

 

I'm not sure how to trace the pin onto the board - I may have to remove the connector...

Below are links to closeups of the front and back around that area.

Also, I'm pretty sure my DMM reads ohms(?) when in diode mode and don't know what CE etc stands for... sorry!

http://www.tapsupply.co.uk/CVR4/pin9front.jpg
http://www.tapsupply.co.uk/CVR4/pin9rear.jpg

 

Ok. this is going to be tough. B, C and E, stands for Base, Collector and Emitter of a transistor.
Hang on. I'll see what I can come up with. Don't loose hope, I never give up. Ever.
Just a bit caught up with an extra work, ( see Studiot's thread ).
Any ways, are you familiar with star delta connection in induction motor.

 

See the png....Notice the arrows pointing to the solder connections.
I want you to check for continuity from the PSU_ON pin to which of these pads have a connection..mark it post a pic
The green Wire i.e.

http://i702.photobucket.com/albums/ww28/Rifaa-ath/edit.png

 

Thanks for being so understanding of my ignorance! Luckily I can use Photoshop!!

Ok, I checked with DMM set at 20k ohms and recorded the resistances at the various solder points..

Here's a results image - http://www.tapsupply.co.uk/CVR4/atxon.jpg

The joint marked "RISE" does just that - the resistance rises like it is charging a cap.