This question might have been asked a million times already but I really couldnt find anything on it. I have a few autometer gauges I need to find a 12Volt source for. Im new to wiring so I really dont know how to find one and right now my car has no motor in it so I cant get any power to it. Can anyone explain to me how I would find a 12v source on the fuse block or an existing wire I can tap into. i think running it off the block would most likely be better so I can hook up a fuse for the gauges. So the long and short of it is any info will help and pics of how to would be awsome. Thanks.

 

The fuse block has two extras, IIRC (I used one for fans and one for mirror with compass, etc).

JamesC

 

So what would i do find the IIRC on my fuse block and plug into it from the back??? Would I be able to use a fuse with it?? What are the ACC on the fuse block for??? As there is 2 ACC spots open on it as well.

 

There are several open slots on the fuse block. Some have ACC, these are for accessories and they only get power when key is on (would work fine for your guages). There are some with BAT, these have power all the time regardless of the key (I use them for interior lighting since I want it to come on with doors open, etc. but before key is on). You can crimp a simple male spade connector on your wire and stick it in these extra slots from the front side.

 

So I stick the wire where the fuse goes then?? Sould I put an inline fuse then as i want to make sure my stuff is protected.

 

Yes - kind of. There aren't any fuses in the slots I mention - they look like fuse slots, but like on the IGN one, there's only one slot, so a fuse would not go in because a fuse has 2 tabs if that makes sense. At least it's this way on my fuse panel.

And yes, I'd use an inline fuse.

 

Its always a good idea to protect the circuit.

 

Can anyone tell me the amp rating on the Accessories as I might have found something I can use that plugs into the fuse block. The onlt thing is its rated for a 10 amp rating and I want to make sure the accessories are the same but Im pretty sure they are a 20amp. Id look at my car but its not at my home.

 

When you use the IGN or BAT terminals on the fuse block, you don't need to use fuses, because they're already fused. The BAT terminals run off the ACC fuse, and the IGN run off the GUAGES fuse.

Pico wiring sells the pigtails for both the BAT and IGN terminals.
BAT cavity 0951pt
IGN cavity 0952pt




Google "pico 0951" or "pico 0952" and click the shopping tab, they're about $2 each.

 

So do these go in the back of the fuse block where the empty slots are??? Im new to wiring so the simple and easy way or explaination would be the best. Sorry guys I know this sounds easy but ive never done it and I just dont need a fire in my car.
Thanks

 

I was looking to add something like this to the fuse block.

http://cgi.ebay.ca/Lot-3-ATC-Add-Cir...item255a4cfffc

Anyone ever used one??? All I need it for is my autometer gauges and from what i read they are all 10amp draws so this will work i hope. I just dont know where to patch it into?? If I use this empty slot or a one being used??

 

You're making things way too complicated. You don't need a saddle tap like that because GM has already taken the initiative and provided you ports for additional circuits. Go pull down your fuse block, you'll have a bunch of fuses with labels identifying what they control, then you'll have several open sockets in the lower left and lower right corners labeled BAT and IGN. BAT sockets are 12v constant, IGN sockets are 12v switched. The pigtails I mentioned earlier snap right into the sockets, or you can use male spade terminals. The BAT terminals run off the ACC fuse, and the IGN run off the GUAGES fuse. The ACC fuse is 20 amps, GAUGES is 10 amps.

You could replace every gauge in your dash with aftermarket gauges, and wire them all to the IGN port without a problem. For that matter, you could tap into the factory gauge lighting circuit and run them off the dash dimmer so they'd work light the factory illumination. Just keep it simple and you'll be fine.

 

Im gonna do it the way you explained for sure as that sounds the easiest by far and will look cleaner. Mine if i Pm you If I get any more questions at all???

Oh and I got my gauge lights se up that way as i tapped into the center console light and now they work on the dimmer.

 

Feel free, but you can probably get a faster response posting to the forum. If you want to make sure I'll see it, just PM me the link to the thread.

 

Great I found tons of places I can get it from but so far it looks like no one is willing to ship to Canada. The search continues

 

Pico is a fairly common brand. You might be able to find a local auto parts store that could order what you need. If nothing else, just use a male spade terminal.

 

Just a note on powering accessories from the taps at the fuse panel. Any item powered from these taps needs to be fused seperately to protect the item being powered in the event of an overload. Never connect any device to power without a fuse of correct rating for that device.

 

Nice edit, I'm sorry but you're wrong.

There are only two ports, 12v constant, 12v switched.

Those ports are protected by fuses that are already in the fuse block. The wiring diagram clearly shows that the ports are downstream of existing fuses. Adding additional fuses is just going to result in the lowest amp fuse in the chain to pop in the event of a problem.

You can test the theory yourself, all you need is a test light. Connect the test light to a ground and one of the IGN ports, turn the key to run the light will come on. Unplug the GAUGES fuse and it goes off.

The same test with the BAT terminals, and the ACC fuse has the same results, except BAT is full time, so it doesn't matter what position the key is in.

Of course this all applies to the later cars, and there's a possibility that early cars might not be wired the same way. The vast majority of my documentation is for the 1991 model year, and sometimes early cars are different.

 

I wasnt able to verify whether what you say is correct or not. My diagram for the 85 is too vague. Thus the edit. One thing I can verify though is that on the 85, the ACC Power circuit is protected by a circuit breaker. I can only assume that this is what the Batt tap out is fed from, as the ACC Power circuit is hot at all times. If this is true, a circuit breaker is not adequate protection for a low current circuit.

As I said before, the key purpose for fusing a circuit is to protect the device itself in the event of an overload. You never connect a device to power without the correct size fuse. You can argue if you like. Ive only been an automotive electrical specialist for 35 years, what do I know.

 

The test I mentioned above would be enough to verify that the fuse feeds the circuit. The 87 diagram I just checked seems to be indicating the exact same thing the 91 diagram I checked earlier before ever posting in this thread. The power into the fuse block is fed by a fusible link, passes through C100, then goes to the ignition switch or directly to the fuse (depending if it's switched or constant), then on to the BAT or IGN terminals.

Assuming the item being connected uses a fuse with a smaller amp rating I could see how that would be relevant. Otherwise the fuse in the block will pop and the one in line to the device is going to be fine.

 

I simply added my Valentine Radar to the 12 volt source wire that plugs into the back of the radio. (yellow wire)

 

Might want to check the amp draw on the radar unit - I'm sure it's not much, but that yellow radio wire is only intended to draw enough juice to maintain radio station settings and clock (which is barely any at all). If the radar device draws any amount of amps, might tax that yellow wire too much.

 

The yellow wire to the radio is 12v switched... Ie it's the power wire for the radio and it's internal amp. The memory wire is the orange 12v constant, and is powered through the ACC fuse, which would probably still be more then sufficient for something with demands that small.

 

Ooops! I had it backwards huh? I'm blaming old age!

 

Lol, camaronewbie is thinking of just about every audio equipment manufacturer in the world. They all use yellow for batt constant and red for ign on. Leave it to GM to be oddballs.

 

..Unless you are dealing with a security system... In which case, they USUALLY use red for constant and yellow for switched. LOL. Interesting topic!

 

OK - well nice to know - doesn't change me being old though!

 

Just out of curiosity; How old do I have to be to be old? Because I'm approaching 40 and still think thats kind of young...

 

Approaching isn't bad, once you hit 40 though you might wanna start shopping around for walkers, Slap an iroc sticker on one or somethin. jk lol

So, ill admit i'm slower than just about anybody... But question

You use a male spade connector for the power at the BAT or ACC empty spot, and run it out the front? you guys are saying its already wired and fused and everything, Whats the pico pigtail for? thanks.

 

what I did, I ran some new wires for my gauges from the battery to the gauges with a fus n between them and a 12V 40A relay in between them.
and the relay gets switched on when the original instrument gets power.

this way the original powerwires only get 0.1A more (wich it should handle fine )
and my new wires ( 2.5mm wire ) can handle more then enough juis trough it

 

I finally tracked down a few of these last night so I will be installing them this week. I hope I dont melt my fuse block LOL

 

Well, I ran the wires straight out of the BAT and ACC out of the front - but I then put inline fuses between the fuse block and the device.

And I guess it's like cars - it's not the age as much as the mileage. I'm 45, young at heart and mind, but I've got alot of miles - so I just can't do the things my heart and mind 'think' I can anymore

 

LOL, I know what you mean! Mileage counts for a lot!

 

Just a quick question theses get plugged into the fuse panel thru the front right as I tired to put them in the from and it was a tight fit and I didnt want to force it yet till I knew for sure.

 

They should plug in the front... Don't force them, take a good look at the key way and make sure they're lined up right.

 

Ok its been awhile since I worked on my car I got the plug in it. I am running 2 of them one for my autometer gauges and one for my MSD. I got another question for everyone. Should I run fuses after the plug before it gets to my gauges and my MSD and if so what amperage should I run for either of them. Thanks again guys for all the help

 

Bump would like to know for the weekend so i can finally finsh the wiring. Thanks

 

See this post... https://www.thirdgen.org/forums/post...54-post18.html

You can go ahead and wire in an inline fuse if you want, but the circuit is already running through existing fuses.

Refer to the documentation for the device you're adding, and fuse it accordingly. If the current draw is larger then the existing fuse in the fuse block, you'll probably need to find a different power source, or use a relay.

 

If these ports a protected by fuses already then ill plug it in and hope for the best as I dont have any power in the car as I havnt got a motor in the car at the moment. Sorry to bug you all the time but im not too good at wiring and I just dont want to set a fire in my car so better to ask then before I do it. thanks Ray