Question about autometer electric gauge install

[mob]

Hey guys, I got a quick question about my electric autometer oil pressure gauge. It says to connect the (i) terminal to the ignition switch or another switched 12v source. First of all I dont know where the ignition switch is, and second I cant just hook it up straight to the positive battery terminal with an inline fuseable link? Can I connect it to the starter solenoid? Which terminal do I connect it to? And if I cannot do that how do I know which wire on the ignition switch is +? And for the light can I connect that to the battery? Or does it have to be the positive wire on the back of the radio or the fuse box?

 

[LiquidGT]

Hook the (I) terminal to a wire that has power when the key is in the on position, this makes the gauge come alive when you turn the key; it doesnt necessarily have to be the ignition switch. If you use the battery the gauge will be on all of the time and drain it. Get a test light to find the right wire.

For the light, hook it up to something that comes on with the parking lights, I use the shifter bulb for the AOD or the ashtray bulb when at the center of the car; I tapped into the headlight switch for the gauges on the pillar pod.

 

[mob]

Ok thanks alot for that, so I can actually hook up the (i) wire to radio correct?

 

[jrichker]

One of the radio power wires is hot all the time to keep the saved settings feature working.
Use blue wire with the black stripe if you decide to tap the radio wiring for power. Here's the link to the rdaio wiring PDF doc. http://forums.stangnet.com/attachments/41724d1137094899-factory-radio-question-ford-radio-wiring.pdf. You will need the Adobe Acrobat viewer which is also a free download – Adobe - Adobe Reader download - All versions


OR:


Diagram courtesy of Tmoss & Stang&2birds

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Mustang FAQ - Engine Information Everyone should bookmark this site.


Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for94-95 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

 

[mob]

Thanks Joe, very helpful as always.

 

[mob]

Ok so I got everything set up, but when I went to look at my radio harness I did not see a blue wire with a black stripe on the stock part of the harness. I have an aftermarket cd player with the aftermarket plug in between to make them work, the colors are the same as in this link:
http://www.installer-parts.com/wires/index.html
so can I just splice it into the red wire?



And also does anyone know which wire on the ashtray light is the power wire? And is alright to run a 14 gauge wire to the light wire?

 

[The Shape]

I can't remeber the color off hand, but I also have the adapter harness between my deck and factory wiring and I used the dimmer power wire in the fatory harness to power my gauge lights. That way the gauges dim with the other dash lights when I roll the dimmer switch back.

 

[mob]

the wire on the new harness should still dim correct? And does anyone know what color wire is the power on the ashtray light bulb?? I would like to get the project done now, Ill try and get a picture of the wires so someone can point it out for me, thanks.

 

[HISSIN50]

No matter what anyone says, you should always test any wires you tap into. This makes quick work of testing that a wire loses voltage as the dimmer is used, or that the correct ashtray light is used. NEVER blindly tap into a circuit (IMHO).

You can test the dimmed function of a wire with either a test light or DMM. One loses brightness as the dimmer is run down and the other becomes numerically lower (respectively).

Good luck.

 

[mob]

Thanks hissin, I confused myself in my last post, I ran the power for the gauge to the radio, the gauge works perfect, I do have a quick question though about the light. Coming out of the ashtray light there is a blue wire and a black one so Im going to guess that the black is the ground, but I am going to get a test light from my work tonight so I can be sure. But my real question is, is there a problem if I run a 14 gauge wire to a 18 guage wire? The wire for the light from the gauge is a 14 and the wire on the ashtray bulb is 18, will it catch fire, blow out, etc. if I connect them and run them like that? I already have everything run onder the console and the light is already grounded I just want to make sure I can connect those two and be fine.

Oh and at idle my pressure is 50 psi. Thats normal right? I searched alittle seems kinda high im about to take it for a drive to see if it follows "the rule of thumb" 10psi for 1k. I just changed my oil with valvoline sae50 because my oil was coming out water thin and my stock sender kept dropping the gauge, im gonna take it for a drive and we'll see

Update: I took it for a drive, it never drops under 50psi, thats the lowest it goes and stays there at idle which is about 800rpm. At about 2000 rpm it goes to about 55-60, at around 3k it goes to about 63-65psi, but at wot past 3krpm it doesnt go past 65psi, thats the highest it goes, seems normal to me from what ive read but if someone can give me some input that would be great, I have yet to see what happens to it though after an hour or so of driving and everything gets real hot, and if someone could help me out on the 14 to 18 gauge wire thing that would help me finish the job, thanks!