Always on ignition wire

Tony8470

Registered User
Got a bunch of autometer gauges ready to go in the car. But the boost gauge requires an always on ignition wire during cranking. To maintain its calibration. Is there one I can tap a relay into? I might as well use that wire to run the relay I have. And run all the gauges off the always on wire/relay.
 
There is an always on wire on the IRCM module that controls the low and high speed fan and other things I cannot remember the colour. If you have a Haynes manual it shows it.(pink maybe?). I tapped into it for something just can;t remember what.
 
Back when mn-12 performance was around, there was a write up on the small intercooler fan kit. It used a red wire with green stripe coming from the engine bay fuse box. I've had a gauge connected to it for a few years now.

Do you think this could be it? I totally forget.
 
Always live as in key off or always live with key on but engine not running?

Ugghh that MN12 install was nasty I never did do it that way, never removed the rad and installed the intercooler fan no problem. I think and I can;t recall I used that wire from the IRCM to energize the relay and powered the fan through the relay from somewhere else. Tapping into that octopus of wires under the main fuse panel was too ugly. Maybe that IRCM wire is hot with ignition switch on, too long ago to remember and no Haynes manual nearby.
 
That is the article. I forgot who had them now. Looks like it's TCCoA.

I'll have to check that wire. But if it isn't, like Les said, it's gonna be a huge pain sorting through every single wire.

I need a wire that is always live when key on engine running, key on engine off. But especially when the engine is cranking. It needs to be off when the key is out though. The meter goes through a calibration when KOEO. But requires a connection to an accessory that is on while cranking. This is difficult, because most, if not all accessories turn off while cranking.

If the meter turns off while cranking, then it will turn back on and recalibrate to the engine running with vacuum. The meter will calibrate that vacuum as 0 psi. And that will be incorrect.
 
If memory serves R/LG will work. Power wire for Ignition circuit (CMP, CKP, Coil, ICM, IRCM)
 
I disconnected the starter wire from the solenoid and turned the key to start with a meter attached to the red/grn wire, and ground. I had 12V potential the entire time.

It looks like this will be the proper wire to actuate the relay I'll use.

I'll have at least 6 autometers in use, so the relay will be required. It will be good to use for future electrical as well.
 
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