2nd Gen Non-Engine/Transmission question on finding a live wire

[CFowler]

where would i find a power source to switch on a relay?i dont realy want to go into the cab and use the cigarette lighter unless nothing else is found under the hood or at the back end. im loking for something that comes on with the key in the on/running possition. thanks carl

 

[MarkMiller]

If you already have a switched source for a gardget you can tap that wire. To do that safely you should get a relay from radio shack that would get its own battery power but be switched on and off by the signal wire you tapped initially.



If you do not have a switched source at all yet the stereo power wire will provide you a source that will work in both accessory and on modes. For a switched power that works with the key in the ON position look to the power window wire.



Do not power any thing off either of those. If you need to supply power to a gadget use a relay. they are cheap and easy to use. Just ask the guy at the local radio shack and the directions for use are on the back of the box.

 

[LanceD]

another wire you can tap is the fuel shutoff solenoid wire

 

[JDecanter]

none

I am certainly not an expert when it comes to DC but I discovered something when hooking up a fuel pressure gauge on my 98 24 valve. When I got everthing done but the wiring, I decided before going any further I would test my gauge.



I hooked the wires to the battery and checked my gauge. To my surprise it worked but only with the key in the on position. I did not question it but put in an in-line fuse and ran the wire through the firewall.

 

[LanceD]

that might kill your batteries, because it will be drawing amps all night long. there is no fuel pressure with the engine off, so it seems the gauge is off too, but the power to the gauge needs to be off also.

 

[Thomas]

another wire you can tap is the fuel shutoff solenoid wire

The original poster has a 2001 Ram in his signature—no fuel shutoff solenoid.

 

[ScottLewis]

If you pull the cover on the power distribution box (on the driver's side fender) you'll likely see a number of vacant slots where optional equipment is meant to be powered. I chose the fog light spot since I didn't have them. Use a spade terminal and plug it right into the hot terminal hole. Add a fuse to the circuit and you're good to go. There are a couple of areas that list as "spare" on the cover diagram.



Dan

 

[CFowler]

thanks to all ,the idea from danavilla is what i am looking for. that is a great place for me to get 12v to switch on a relay for my compressor. thanks- carl

 

[ScottLewis]

If you're really tricky, you could even install the relay right in one of the unused relay spots. Would involve getting in a bit deeper than I went on my '98 box though.



Dan

 

[CFowler]

yeah,tricky thats all unexplored area to me, but thats the way i would like to do it though. neat, professional job. its 9 degrees out side now i think ill wait a few daws to finish my air horn installation. thank you for your help. carl

 

[wcjp]

For my 06' Exhaust Brake I found a neat little gadget thing at Autozone. Pulled the 10amp fuse for the seatbelt. Plugged in the double fuse w/lead into the fuse box. Plug in original fuse. Wire relay to the lead. Plug in optional fuse. Since this was trigger voltage, I used a 3amp fuse. I don't know the exact name of the part. It was about 3-4dollars. I dremelled a small hole in fuse box to exit the wire from the lead. Very easy to do without splicing any wiring. Also, very reversible.

 

[Dave M]

For my 06' Exhaust Brake I found a neat little gadget thing at Autozone. Pulled the 10amp fuse for the seatbelt. Plugged in the double fuse w/lead into the fuse box. Plug in original fuse. Wire relay to the lead. Plug in optional fuse. Since this was trigger voltage, I used a 3amp fuse. I don't know the exact name of the part. It was about 3-4dollars. I dremelled a small hole in fuse box to exit the wire from the lead. Very easy to do without splicing any wiring. Also, very reversible.

Here is an add a fuse circuit like I used for powering the lights to my gauges from the dash fuse panel:



Parts Express: Littelfuse Add-A-Circuit Fuseholder for ATO/ATC Fuses



Here is another one:



http://www.sportys.com/acb/showdetl.cfm?&DID=10&Product_ID=801



Apparently Autozone sells one also.



Be sure to get a min fuse type for use in the dash fuse panel not ATO.

 

[CFowler]

danavilla,i only found live circuits in the dist. box. i did have to use a add a fuse thing some one else mentioned and get power from the fuse panel inside the cab. thanks to all of you -carl