It's for the dash lights.
I would add another inline fuse for the CD player.
Plug it onto the ACC terminal.

 

Dean, what yr is that fuse box for?

 

Dean, what yr is that fuse box for?

I *think* it's my 69 but could be a picture I snagged from here.

I notice though that the "little fuse" is not
"to the left of the fuse for the guages"

 

But can I get a 10 amp fuse to fit the little slot? Thats the fuse I was talking about but that block in the pic is laid out different than mine.

 

Why do you want to use the dash light fuse position when there is a place to plug in an accessory wire?
(just curious)

Here is the fuse panel from my 70

 

That circuit is fed from the tail light circuit. The fuse is sized as it is so that it is not possible to install a higher amp fuse. You can connect things like aftermarket gauge lighting, auto console shift indicator light... You should not jumper around that fuse or connect a CD player to it. For safety reasons leave the tail light/dash light circuit as designed. Power that CD from ACC BAT terminals.

Dean
The top fuse block is a 71 or later, but not for a Chevelle. The bottom fuse block may be in a 70 but could it be from a 71? Just curious because the 70 dash harness has the TCS circuit on the top fuse with the A/C, for 71 the TCS moved to the radio fuse.

 

I removed it from a 70 SS LS6 that I parted out but who knows if it was original or not.

Now I'm curious as to where I got that top picture.

 

Nothing about my fuse block is staying the way the factory made it. I cut all the wires off and took it apart. I have rewired a couple of the circuts inside of it, including the small fuse. Now, the small fuse is constant hot fed directly off of the fusible link coming into the block. I am trying to figure out what fuses to use for what and I almost have more electronics than I have fuses for. I may change the way I have the small fuse wired and use it for console lighting. I am not pressed on using the little fuse for the radio, but if I could, things may just be a little easier for me. I want the radio to be on a fused power source. The plugs on the front of the fuse block are fused, but they run off of the same fuses as larger accessories, this could be a danger to the smaller item on the circut (my expensive CD player). The headlights were a cause of an electrical fire in my explorer and the radio was the cause of an electrical fire on my buddy's jeep that we put a sound system in. I cant have anything like this happening in my 'velle.

 

But really, I cant find a larger than 3A fuse to fit in that slot? What is this type of fuse called? Im sure some fuse company somewhere makes these little fuses with nice thick chunks of metal in them instead of that little fillament in there.

 

You are really making a lot of work for yourself that may not have any real payback. The OEM fuse block was actually pretty well engineered for it's time.

If you really want fire protection I would recommend a power distribution box up front with master fuses and relays for high power items like headlights.

If you really want to change everything around why stick with the old school glass fuses? There are any number of modern ATM fuse panels on the market with a lot more circuits and fuses that have to more suitable to a re-design than the OEM panel.

 

I have relays for the H4 headlights that draw their power from their own fuse on the fuse block. Lesson learned. The only real change I am making to the fuse block is bridging this little fuse to draw power from elsewere in the block as opposed to somewhere in the harness. I have made some of the fused outputs larger and many items are going to different circuts. I am reusing my factory fuse block, firewall bulkhead connector, and column sockets. The rear lighting is on its own harness and so is the console. These are factory harnesses and attach to the main harness via original sockets.

To answer the question "why?":

a) rewiring factory stuff like this is cool
b) its cheap

Yes, a fuse block with blade type fuses is cheap. But the one in my car was free and already fits perfectly. Painless sells their harnesses with firewall adapters and factory sockets for over four hundred dollars. Other companies offer products for even more. I have spent fourty five dollars on wire. Thats the total cost of my custom fit eight circuit harness with pre wired turn signal flasher and GM connectors. Thats at least a hundred bucks on ebay and nothing is learned by doing it. And let me mention again that it fits the firewall perfectly.

 

Do y'all suppose I could use the little fuse (stock 3A) for domelight, console light, and reverse lights instead of attempting to use a bigger fuse for a radio?

A cool thing about the factory fuse blocks is that they are relayless. Acc. and Ign. hot fuses on many aftermarket systems are powered by relays. GM does this mechanically through the column on our cars.

 

I have relays for the H4 headlights that draw their power from their own fuse on the fuse block.

Why? It would be better to put headlamps on a circuit breaker anyways.

Do y'all suppose I could use the little fuse (stock 3A) for domelight, console light, and reverse lights instead of attempting to use a bigger fuse for a radio?

All of that will draw to much and blow the fuse. Do you plan on having any dash lights? You can get higher amp fuses, try here http://www.digi-key.com

 

Dean and Elree, thanks for the explanation on the fuse box's.

 

No, no dash lights. The only lights inside the vehicle are the dome light and the lights (2) behind the shift indicator on the console. The relays for the headlights pull power from a seperate source than the power coming from the dimmer switch that activates them. They are 5-wire relays (there are two of them, one is high beam one is low beam). Each has a ground, a power input, an acc. power input which turns them on (from dimmer switch), and two power outputs (one for each bulb). The reason for that is that the higher wattage bulbs overheat the stock headlight wiring, and in the case of my explorer they can catch on fire. The relays seperate the headlight powerdraw from the rest of the harness, keeping it safe. It is still a must to fuse the power input to the relays or use a circuit breaker. Check out:

www.suvlights.com

Thats where my headlight harness came from. I took it off my explorer when I traded it in. It sat in my garage for years before I got the idea to modify it for my chevelle.

 

I would still put them on a breaker, it would be no fun to try and change that fuse on the side of the road in the dark, plus it would give you another space in your fuse box.

 

On the breaker line of thought... I know that you can get maxi-ATM style circuit breakers in either push to reset of self reset types. I have 30A self reset type breakers on my headlight relay power feeds. Headlight power is a safety issue and pulsing on/off is much preferred to just going completely out on a dark mountain road. I would have to look it up later to find the supplier I used.

I understand the "cheap" and "cool" factors... but to completely toss out the factory design is where I get lost. I replaced my fuse block with a new OEM type block. One of the fuses of course feeds the radio, and not surprisingly the new radio required a higher current than the old system provided. So I replaced that one wire with a larger guage wire along with the higher rated fuse. But it is otherwise setup just like stock. Should this need trouble shooting in the future there will be wiring diagrams and such to assist. I pity the poor person who has to figure out from scratch what circuits run where if they are all changed.

That small fuse was there originally because the power in to the headlight switch is wired and protected at a very current level. The dash lights did not require this high level nor it's wiring, so the smaller fuse which enabled smaller wiring to be used.

 

I turned my stock fuse block into a basic 8 circuit harness after looking at the EZ2Wire 8 circuit harnesses on ebay for ninety dollars. The fuse block has fourteen wires in and out of it. Originally, it had 15, but one of them was the input for the small fuse, which is not bridged to another circuit. There are four power inputs (fusible link in, ign. hot, and 2 acc. hot). The ten outputs are as follows:

1) brake lights - constant hot
2) headlights- constant hot
3) column - constant hot
4) fan - acc. hot
5) wiper - acc. hot
6) radio - acc. hot
7) ignition - ign. hot
8) guages - ign. hot
9) output from small fuse
10) output from flasher

I may reconsider the headlights infavor of a self-resetting breaker. Where can I get one of these?

 

I may reconsider the headlights infavor of a self-resetting breaker. Where can I get one of these?

You can get them at some auto part stores. Jegs has some too. Heres some from Americanautowire. They come in several styles

http://www.americanautowire.com/products/Light_Ignition_and_Door_Switches.cfm