Dodge Cummins Diesel Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
588 Posts
Discussion Starter · #1 ·
Hi CF! I know this may seem like a dumb question but here I go. I installed and mounted my Isspro EV2 rail pressure gauge using the Isspro harness and the gauge isn't getting a reading/movement. All I have hooked up to the orange plug is the green and black wires from the harness. Does the gauge need the wire from the trucks ignition for the gauge to work? I was under the assumption that the 3 additional wires hooking up to the gauge from the trucks ignition,dimmer and ground was just for the gauge lighting. I double checked the Isspro harness as I read that those could be mistakenly installed wrong. Thanks for any info!
 

·
Registered
Joined
·
2,840 Posts
Directions indicate what wire is what... why not hook them up like isspro says?
 

·
Vendor
Joined
·
15,046 Posts
Follow directions. Needs the power to read what the harness is saying.
 

·
Registered
Joined
·
58 Posts
It also needs a ground...to satisfy basic electronics. Read the directions.....
 

·
Registered
Joined
·
588 Posts
Discussion Starter · #5 ·
Directions indicate what wire is what... why not hook them up like isspro says?
Haha...thanks. No where does it say that I must hook up those other wires for the gauge to operate. If so why weren't they included in the kit. My Autometer turbo gauge doesn't need power from my truck to operate. Only needs power and other wires for illuminating.
 

·
Registered
Joined
·
58 Posts
I just installed an new fuel pressure gauge...It does say to hook up all of the wires. There is no breakdown of only install x wire for x functions. It says hook up power, ground, and your data input wires. Why would you think to not hook up all of the wires like the directions say?
 

·
Registered
Joined
·
2,840 Posts
I just installed an new fuel pressure gauge...It does say to hook up all of the wires. There is no breakdown of only install x wire for x functions. It says hook up power, ground, and your data input wires. Why would you think to not hook up all of the wires like the directions say?
Ya makes no sense to me either.
 

·
Registered
Joined
·
58 Posts
From the instructions:

"Connect the red, orange and black wires to the orange connector as described above, in positions 1, 2,
and 3 respectively. Slide the white dust cover over the orange connector once the wires are securely
installed. NOTE: The gauge backlighting will only illuminate if both the ignition supply AND the
backlighting circuits are on."
 
  • Like
Reactions: tryNto

·
Registered
Joined
·
588 Posts
Discussion Starter · #10 ·
Thanks for the help, I assumed that if those wires were needed they would've been included with the wire harness like the Autometer gauges did. I guess the difference between my boost gauge and rail pressure garage is the boost is a mechanical gauge and the RP is electric. I'll head out to pick up some 16 gauge wiring.
 
  • Like
Reactions: 02smokin

·
Registered
Joined
·
58 Posts
Thanks for the help, I assumed that if those wires were needed they would've been included with the wire harness like the Autometer gauges did. I guess the difference between my boost gauge and rail pressure garage is the boost is a mechanical gauge and the RP is electric. I'll head out to pick up some 16 gauge wiring.
That gauge should have come with a black, orange, and red wire. I have wire out the yazzoo with from my gauges. Look in your packaging again. It should be coiled up and wrapped with painters tape in the box with the gauge.
 

·
Registered
Joined
·
2,840 Posts
That gauge should have come with a black, orange, and red wire. I have wire out the yazzoo with from my gauges. Look in your packaging again. It should be coiled up and wrapped with painters tape in the box with the gauge.
This is correct, I’ve installed 3 of these gauges on different trucks and the package has always had all wiring included.
 

·
Registered
Joined
·
588 Posts
Discussion Starter · #13 ·
I'll check again but I also moved while in the process of installing my gauges and somehow ended up misplacing the factory harness adaptor so I'm imagining the other wires are hanging out with the harness wiring...
 

·
Ducati M.
Joined
·
6,701 Posts
Or you can order the r72022 dimmer harness. Because of those I have now 6 loops of those red/orange/black wires laying around. I like the dimmer because I like having my gauge backlighting on all the time, but not full brightness.
 
  • Like
Reactions: dunerking

·
Registered
Joined
·
588 Posts
Discussion Starter · #15 ·
Thanks,I guess I'll be ordering that harness as well.
 

·
Registered
Joined
·
58 Posts
Or you can order the r72022 dimmer harness. Because of those I have now 6 loops of those red/orange/black wires laying around. I like the dimmer because I like having my gauge backlighting on all the time, but not full brightness.
I never really understood the dimmer harness. I have my wired to my dimmer switch and the gauges dim with the rest of my indash gauges. Ive wondered if I was I was supplying less power to the gauges...but they dim and no issues so far.
 
  • Like
Reactions: brooklyn 12

·
Ducati M.
Joined
·
6,701 Posts
Diesel manor supplies them with their gauge kits, and when I wired my 4th gen I misscut the dimmer harness, and decided to heck with it, and wired it independent of the lighting switch, and I’ve never regretted it. I have them set for the nighttime brightness of my dash, and they’ve never been any kind of problem. It’s the biggest reason I’m wiring my car that way; my 1st gen is wired to the factory dimmer, and if I hadn’t put matching leds in the cluster they’d be way brighter, but at the same time I have no issues with that setup either.
 
1 - 17 of 17 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top