Couple quick wiring questions

**elimenohpee** · 08-05-2007, 02:52 AM

I have 2 quick questions:

1. I want to tap in the acc wire behind the radio to power on the psu. Now, should I tap the wire coming from the car's original harness, or from the acc wire coming out of the hu? Or does it matter?

2. Should I use a relay when connecting to the acc line?

**greatwhite** · 08-05-2007, 09:04 AM

Originally Posted by elimenohpee

I have 2 quick questions:

1. I want to tap in the acc wire behind the radio to power on the psu. Now, should I tap the wire coming from the car's original harness, or from the acc wire coming out of the hu? Or does it matter?

No No No!

Only use the Acc wire in the stock harness for the sensing in an intelligent PSU. The guage is not thick enough to safely provide enough current to a PSU. Run a decent wire from the battery or fuse box for safe, clean power.

Originally Posted by elimenohpee

2. Should I use a relay when connecting to the acc line?

Not required. see answer 1. You can use a relay in conjuunction with the acc feed to power on a PSU through your new wire if you wish. If you don't understand what this means, please read a little one basic wiring and componenets before proceeding.

Google is your freind.

Good luck

**elimenohpee** · 08-07-2007, 12:03 AM

Originally Posted by greatwhite

No No No!

Only use the Acc wire in the stock harness for the sensing in an intelligent PSU. The guage is not thick enough to safely provide enough current to a PSU. Run a decent wire from the battery or fuse box for safe, clean power.

Not required. see answer 1. You can use a relay in conjuunction with the acc feed to power on a PSU through your new wire if you wish. If you don't understand what this means, please read a little one basic wiring and componenets before proceeding.

Google is your freind.

Good luck

NO no, I wasn't going to draw power from the acc line, I was going to use it as the 'turn on' wire for the psu. I'm going to run a separate wire from the battery for the main power line. The question was more or less to tap the acc line from the harness of the radio, or the harness of the car. I'll just tap it from the harness of the radio (if that makes sense). I understand the use of relays, I just didn't know if thats how everyone was wiring it up. I could get away without using one, but if everyone agrees it safer to use it, then I'll throw one in.

**slinkytoy** · 08-07-2007, 12:32 AM

a relay is really the best way to go. Due to that fact that when you hit it with 12 volts it gives you the 12 volt turn on that you are looking for. But pulling a ACC from the wiring harness is just as good also. Mine is off a relay jsut becasue i got so much turn on stuff going on in my truck i just added a relay to the ACC on my PS. Hope that helps yea out.