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Underhood 12v+ keyed power

HighSierra86

HighSierra86

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Anyone have a good place under the hood to steal 12v+ keyed power? I hate splicing into any main harness' but I need an aux power source for my LP relay, and i hate using those cheaters that you stick in the fuse box.

Thanks for any help
Nick
 
I need to look again, but I thought there is a single packard style connector that is hot with key on. Its under steering column area somewhere.
Are you going to incorperate the safety of loss of oil psi kills the LP?
 
For LP tie into the normal OPS feed to lift pump, instead of powering lift use that to energize the control coil of your new relay and have the heavy load side of the relay power the lift poump fed from the aux terminal @ the underhood relay center. That way you will still have OPS protection/control in event of a crash/fire accident OPS contacts can handle the light load of a relays control coil, vs. pulling lift pump load.

I don't recommend tying into a ignition switch source to control the power to the lift pump, as in accident if you get knocked out, or forget in "heat of moment" to switch off the ignition, then possibly with the lift still energized and a broken line you could feed fuel to a fire.
 
So Tim if the OPS fails on an OBD2 truck it still runs the lift pump off the ECM. Wouldn't that mean that the LP would run on the ECM in the event of a wreck?
 
Burning oil said:
I need to look again, but I thought there is a single packard style connector that is hot with key on. Its under steering column area somewhere.
Are you going to incorperate the safety of loss of oil psi kills the LP?
Click to expand...

I actually splurged a few years ago when business was good and purchased a LP relay kit from kennedy. It was pricy but a clean and well built settup. Only complaint was for ignition power they gave you a tiny brass tab to jam under one of the fuses. At the time I installed it I wasnt happy but couldnt really find a quick easy source of keyed power.

Well my suspicions were correct....while on the way to the hospital to see a friend I lost fuel pressure on the highway. Had to pull over and plug back into the factory harness I left on the frame rail. Didnt spend much time trying to diagnose the problem as i was in a hurry, but i knew the box wasnt getting power.

Needless to say ive been running with the stock harness ever since until I get a chance to find a more reliable source of power. I really hate having wires all over the place, coming out of the fuse pannel, etc. So i still might just end up splicing into a harness somewhere. Ill check quick under the dash for a stray plug, but thats opening another can of worms. I really need to get in there and clean up all the halfassed wireing jobs from the POs.

Thanks for the tips, If i get some time today Ill see what I can find....

-Nick
 
It is the F-SOL fuse. I used Kennedy's LP/OPS harness also. Been there for more than 3 yrs using the provide fuse tap.
 
Power wire on 96& up

Went out and took a pic of wire I was thinking of. In the picture its in center and is a male packard. The wire is in the big bundle coming out of fuse box under hood. It should only be hot with key on.

power wire 001.jpg
 
ak diesel driver said:
So Tim if the OPS fails on an OBD2 truck it still runs the lift pump off the ECM. Wouldn't that mean that the LP would run on the ECM in the event of a wreck?
Click to expand...

if engine was still running then yes as PCM would still see rpm & need for fuel and keep it energized along with the OPS still seeing oil pressure, once engine rpm stops so does lift power via PCM & power via OPS once oil pressure bleeds off, that is why when priming a OBD-II fuel filter you have to keep cycling the ignition key on & off as PCM will only allow momentary lift pump power to a non rotating engine maybe 6 seconds or so.
 
Burning oil said:
Went out and took a pic of wire I was thinking of. In the picture its in center and is a male packard. The wire is in the big bundle coming out of fuse box under hood. It should only be hot with key on.

View attachment 27728
Click to expand...

Thats exactly what I was looking for. I have the same plug on my truck yet it has no power. Key off or on. Does anyone maybe have a schematic which shows where it draws power from? Fuses are all good...none missing with the exception of the abs
 
HighSierra86 said:
Thats exactly what I was looking for. I have the same plug on my truck yet it has no power. Key off or on. Does anyone maybe have a schematic which shows where it draws power from? Fuses are all good...none missing with the exception of the abs
Click to expand...

Give David a PM.
 
What are you looking for power for ? Energized power needs to come from the OPS . The power side of the circut that you want to complete to the LP can come right from the battery, it does not need to be keyed.
 
Acesneights1 said:
What are you looking for power for ? Energized power needs to come from the OPS . The power side of the circut that you want to complete to the LP can come right from the battery, it does not need to be keyed.
Click to expand...

Going by the directions given with the relay kit....It already has constant battery voltage, but this one lead needs keyed power
 
That's weird. None of the ones I ever put together needed keyed power. The Sol was activated by the OPS and completed the circuit of LP->Batt.
 
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