re-wiring to use batteries???

[johndeverill]

Hi all,

There is probably a very straightforward answer to this so you will have to excuse my ignorance.

I have a PC fan controller that I want to run on batteries. It came with the standard 12v,-ve,-ve,5v molex connector.

I connected the 12v wire to a 12v battery pack +ve. I then connected another wire from the +ve to a 5v regulator and onto the 5v wire. I then connected the 2 ground wires and the regulator ground to the battery pack -ve terminal.

The LCD backlight comes on and that's it. I am going to be installing this in my car so should all ground connections go to the body earth of the car?

If anyone can help with this it would be great as I'm sure it's a simple problem that I just don't have the knowledge to fix.

Thanks in advance

John

 

[ante1]

Hi John,

If you can, post the circuit you have made so we can see what’s wrong!
BTW, have you tested this fan controller in its normal environment to make sure it’s OK?

 

[johndeverill]

Hi Ante,

Yup it worked OK connected to the PC.

The circuit below is a bit simplistic but is colour coded as per the PC molex connectors.

View attachment 38537

 

[Staigen1]

Hi, sorry to interrupt

One big error here, the yellow wire in a standard computer molex connector is 12V, and the red one is 5V!
Maybee also the 5V regulator is connected wrong then! Check!

//Staigen

 

[ante1]

Hi John,

Yes Staigen is correct! If you rewire it the right way and have a bit of luck here (if nothing got destroyed) it should work fine!