Where is the ignition wire on a LMM?

floridamax · 03-12-2009, 10:37 AM

This truck does not have a ignition switched power outlet, they are always powered at all time. I found under the dash a wire that has power only when the ignition is on but it's pretty small and Im afraid to put a load on it. Anyone has found a bigger size wire ignition switched on a LMM?

**Six-Gun-Todd** · 03-12-2009, 10:49 AM

Quote:

Originally Posted by floridamax

This truck does not have a ignition switched power outlet, they are always powered at all time. I found under the dash a wire that has power only when the ignition is on but it's pretty small and Im afraid to put a load on it. Anyone has found a bigger size wire ignition switched on a LMM?

Depends....what are you trying to power ? There are a bunch of circuits labeled in the engine bay fuse box as ignition....just pick a jumper fuse up from the local auto parts store....

**MMLMM** · 03-12-2009, 10:50 AM

Quote:

Originally Posted by floridamax

This truck does not have a ignition switched power outlet, they are always powered at all time. I found under the dash a wire that has power only when the ignition is on but it's pretty small and Im afraid to put a load on it. Anyone has found a bigger size wire ignition switched on a LMM?

underhood fuse box there are a few, I'll go look in a few. I have 2 tap ins there and they are switched power.

also if you are gonna be loading any wires you better put in a relay....

floridamax · 03-12-2009, 10:55 AM

Its not gonna be a big load, just gps, cell phone charger, laptop and little stuff like that but the wire was way too small to use it as ignition. Thanks guys I think Ill just run a new wire from the main fuse box under the hood and be on the safe side. at the same time i will hook up one of the power outlet so i will have one switched with the ignition.

Beaner242 · 03-12-2009, 11:31 AM

I hooked up my compressor with a relay to the underhood fuse panel, I dont remember the fuse number. I used the add a circuit or whatever its calles from autozone. Everytime I hook it up my DIC reads that i have a prob with trailer wiring and my cruise wont work? Unhook the add a fues and put the fuse back in normal and it goes away.

K9Duramax · 03-12-2009, 11:40 AM

Quote:

Originally Posted by floridamax

Its not gonna be a big load, just gps, cell phone charger, laptop and little stuff like that but the wire was way too small to use it as ignition. Thanks guys I think Ill just run a new wire from the main fuse box under the hood and be on the safe side. at the same time i will hook up one of the power outlet so i will have one switched with the ignition.

Why not run a relay and use the small ign. wire under your dash to trigger it on??

K9Duramax · 03-12-2009, 11:42 AM

Quote:

Originally Posted by Beaner242

I hooked up my compressor with a relay to the underhood fuse panel, I dont remember the fuse number. I used the add a circuit or whatever its calles from autozone. Everytime I hook it up my DIC reads that i have a prob with trailer wiring and my cruise wont work? Unhook the add a fues and put the fuse back in normal and it goes away.

Where are u getting the 12v Constant from- fuse block or positive battery jct. block? Should get it from the jct. block or from the pos. side of the battery- if that's what you are doing try a different fuse under the block for your relay trigger.

**AlligatorPerformance** · 03-12-2009, 12:26 PM

Pink wire in the middle of the 100 wire harness under the dash. You will find at least 3 pink wires in there, it is in the middle. Use a LED test light when you probe for that wire.

Beaner242 · 03-12-2009, 01:32 PM

Quote:

Originally Posted by K9Duramax

Where are u getting the 12v Constant from- fuse block or positive battery jct. block? Should get it from the jct. block or from the pos. side of the battery- if that's what you are doing try a different fuse under the block for your relay trigger.

Constant is running off the junction block. I'll check the fuse I used when I get off work. Its the only one I found that was switched. I would actually like to find one that only had power when the engine is running.

**MMLMM** · 03-12-2009, 01:37 PM

Quote:

Originally Posted by Beaner242

Constant is running off the junction block. I'll check the fuse I used when I get off work. Its the only one I found that was switched. I would actually like to find one that only had power when the engine is running.

this has been done with lift pumps....

Run a power from battery, and put a oil pressure switch on a relay. Then you will only have power when oil pressure is up (engine running)...And your not taping into the other elec. components.