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12 volt Power souce

Power source

I would like help to locate an ignition wire to power a small dash mounted back up camera for a 2007 Chev. Suburban?

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Re: 12 volt Power souce

I don't recall there being a switched power source in the back, but I'm not 100% sure. Does it have the cigarette lighter jack in the back (for an air pump, etc)? That may or may not switch with the ignition.

If you want it to come on only with the backup lights, just tap into the power wire for the backup lights themselves.

Posted on Jan 08, 2008

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I just built a new computer and when i tried to boot it up nothing happened. The Corsair ax850 PSU isn't even "humming" or giving any indication that it has power. The 110v wall plug has power....

You won't get any 'fireworks' or 'smoke', widsss.

A) Make sure the Power On switch is connected to the correct pins, in the Front Panel header on the motherboard.

(The Front Panel is the plastic front of your computer where the Power On button, HarDDrive activity LED, Power On LED, etc., is located.
The pin area on the motherboard that the Front Panel cables (Wires) plug into, is the Front Panel header)

Either you do not have
1) The correct cables (Wires) plugged into the motherboard from the Front Panel,
2) A bad Power On switch,
3) A bad Power Supply
Even if the Power Supply is brand new, it can still be a dud.

There is a simple test to see if the problem may be the Power On switch, or the Power Supply.
After you have made sure the problem is not incorrectly attaching the wrong wires, from the Front Panel to the motherboard, reply back in a Comment, and I'll detail out the simple test for you if you wish.

B) Make sure the 4-pin ATX +12 volt power cable is plugged in, if your motherboard uses it.
It's power for the Processor.

C) Your motherboard may not use a 4-pin +12 volt power cable. It may require more power.
In this case an 8-pin EPS +12 volt power cable is used. The equivalent of two 4-pin +12 volt power cables.

1) Red wires are 5 volt
2) Yellow wires are 12 volt
3) ANY Black wire you see is a Ground wire )

I await your findings.

Mar 07, 2011 | CORSAIR Professional AX850 ATX12V and...

1 Answer

Ref ASTEC power supply from old computer model SA 147-3505 I can pick up the logic 5 volts but not the +12 volts and -12 volts .FAN not energised so I guess there needs to be an elec link via the computer...

You can jumper on an ATX power supply by using a wire to connect pin 4 (green wire) to any of the grounds on the 20 pin ATX connector. The grounds are normally a black wire. You will need to put some sort of load on the power supply such as a hard drive to keep it running.

Feb 25, 2011 | Dell PWR,SUPPLY,145 WATTS,ASTEC SA150-3411...

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The power supply came with no manual. There is no P IV power lead. There are two aux power leads. (1) four wire (O,B,R,Y) and (1) six wire lead (B,Y,B,Y,B,Y) The original power supply P IV lead has four...

As you've noted you need two Black wires (Ground), and two Yellow wires (12 Volt),
for a 4-pin ATX +12 Volt power cable,

If you are not using the 6-pin PCI Express power cable,

,rob the 4-pin ATX +12 Volt power cable connector, and wires from the old power supply.

Splice the wires of the 6-pin PCI Express to them.

Orange wires are 3.3 Volt
Red wires are 5 Volt
Yellow wires are 12 Volt
Black wires are Ground wires.

You need two Yellow wires, and two Black wires.

Or if you have a spare 4-pin standard Peripheral power cable from the power supply,

,buy and use an adapter power cable.

Nov 27, 2010 | Coolmax Technology COOLMAX M500B 500W EPS...

1 Answer

I am trying to troubleshoot whether or not my ultra x2 connect 550 watt power supply is bad. When you press the power button on the computer, the light flashes and then noth9ing else happens. The light...

Well here is a way to check your power supply, on your hard drive connector using your volt meter and measuring from ground. this would be using one of two middle connectors it should measure +5 VDC on the red wire and + 12 VDC on the yellow wire. If these voltages are good then we got to see if the power supply is producing the -12VDC voltage. This voltage is ussed by the syustemboard on pin 14 of a 24 pin power supply. I would recommend not having your system board plugged in while measuring these votlages, but the power supply may need a load, I would plug in the cdrom.. Below are a couple of picture to explain this and a link to a website that has this documented.

dfish26_1.jpg The 24 pin main power connector was added in ATX12V 2.0 to provide extra power needed by PCI Express slots. The older 20 pin main power cable only has one 12 volt line. The new 24 pin connector added one line apiece for ground, 3.3, 5, and 12 volts. The extra pins made the auxiliary power cable unnecessary so most ATX12V 2.x power supplies don't have them. The 24 pin connector is polarized so it can only be plugged in pointing in the correct direction.
Pinout Pins 1 through 12 Pins 13 through 24 Description Wire color Pin number Pin number Wire color Description +3.3 volts orange 1 13 orange +3.3 volts +3.3 volts orange 2 14 blue -12 volts ground black 3 15 black ground +5 volts red 4 16 green PS_ON# ground black 5 17 black ground +5 volts red 6 18 black ground ground black 7 19 black ground PWR_OK gray 8 20 white -5 volts (optional) VSB +5 volts purple 9 21 red +5 volts +12 volts yellow 10 22 red +5 volts +12 volts yellow 11 23 red +5 volts +3.3 volts orange 12 24 black ground
Good Luck I hope this helps.

Nov 19, 2010 | PSA Ultra X2 Connect (ULT31851) 550-Watt...

1 Answer

Which wire is the 'ON-PS' switch for the Astec Model SA145-3435 power supply?

I found out that the AT supply SA145-3435 does not have a switch wire like an ATX supply. I have a SA145-3435 my self. To get it to work it must have a +5 volt load (BLACK and RED) and a +12 volt load (BLACK and YELLOW). If it does not have both of these loads it will power down after a 2 second delay when you plug it up. I used 2 small 12 volt bulbs. One for the 12 volt line and one for the 5 volt line. The type of blub I used was a #94 I got from the auto parts store.

Oct 01, 2009 | Dell 145W Power Supply SA145-3435...

1 Answer

Adding trailerbrakes to a 24 volt truck

Are your electric brakes rated for 12 volt or 24 volt, that is the question. YOu have to supply the voltage at whatever the brakes are rated for.

Apr 15, 2009 | IBM LENOVO 24V POWER SUPPLY 42L0085 Power...

1 Answer

Power supply suddenly 'dead'

You check the power supply using multimeter. but before everything make sure the you are getting power from the power outlet.

Here is how you can check the power supply with multimeter

If the wall outlet and the power cord are good, make sure the connection at the motherboard is secure. Then you may have to face the fact that the power supply itself is bad. If you have a multimeter, you can test the power supply output before purchasing a new one. Simply follow these steps:
  1. Turn off the PC, but do not unplug it. Open the system unit. Set the multimeter to read DC volts in the next range higher than 12 volts. Locate a power connector similar to the hard drive (or CD-ROM drive connector that is unused) and turn on the PC.
  2. You can also unplug a drive connector and use it. Turn on the PC and insert the BLACK probe into the power connector on one of the BLACK wires. Touch the RED probe to the YELLOW wire on the power connector.
  3. The multimeter reading should be +12 volts. Now touch the RED probe to the RED wire and the reading should be +5 volts. If no readings or different readings occurred, you’ll have to replace the power supply. If the readings were correct, you should check the P8 or P9 connectors at the motherboard. These connectors may also be named P4 and P5. To check these connectors, perform the following:
    • Insert the BLACK probe into P8 at one of the BLACK wires. Insert the RED probe into the P8 connector at the RED wire. The reading on the multimeter should be +5 volts.
    • Check the power going to the motherboard connections by inserting the RED probe into P8 at the YELLOW wire and you should get +12 volts. Leave the BLACK wire touching the BLACK wire at the P8 connector. Check the BLUE wire and the reading should be a -12 volts.
    • Now move the BLACK probe to the BLACK wire on the P9 connector. Test the WHITE wire by inserting the RED probe and the reading should be -5 volts. Check the RED wires on the P9 connector and you should get +5 volts on each red wire. You won’t get exactly 5 or 12 volts, but the readings will be very close, such as 5.02 volts.
    • If the Power Supply is a couple of volts off in either direction, such as when the RED wire should be reading -5 volts but it reads -8 volts, or if there are no readings, replace the power supply.

Mar 22, 2009 | System Power Supplies

1 Answer

Busted component

Getting a schematic is rather doubtful. You might be able to get a general idea of the circuit from somewhere on the 'net.

Was the power supply dead?

ATX style power supplies have both a standby and main section. The standby supplies a low current +5 volts to a small portion of the motherboard.

If the component failure is in this section, this standby voltage will be missing or incorrect, and the computer will be dead- won't power on at all.

I've seen a number of catastrophic failures in this standby circuit, and repair isn't suggested or economically feasible, especially as some parts often poof beyond identification.

When the pwr button is pushed, the main section comes on, and supplies +5 (Red wires), +12 (Yellow wires), +3.3 (Orange wires), -5, -12. Look here for this info

Voltages are precisely regulated, and any substantial deviation (more than a few 10ths of a volt) indicate a problem, especially on the +5 & +3.3 lines.

Jul 07, 2008 | Okia / 450-Watt / ATX / 80mm Fan /...

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