Could I fry my electrical system?????

[NJB71]

I know I should just spend $ and buy a new wire harness, but cash is being used elsewhere...so question is this, stock harness...w/ electric choke, tach,mojave heater, and now stereo all running off clip plug ins to fuse box, could I run into trouble? and yes it looks messy behind the dash

 

[70_Steve]

Yes, it's possible to add enought auxiliary stuff to the fuse box that you overload some wires, and cause some damage. Why not mount an extra fuse box. Only a couple dollars for a 6, 8, 10 circuit fuse box, and some wire. Mount the fuse box anywhere it's convient for you. Run the wire from the battery, bypassing all the stock wiring.

 

[Steve83]

If you add these accessories correctly (using proper fuses), there's no chance of damaging the harness. That's the purpose of a fuse: to be weaker than the wiring. At most, you'd burn a fusible link wire, or overload the alternator if you turn them all on at the same time.

Adding a fuse block is certainly better.

 

[NJB71]

xtra fuse box, great idea TY-question follow up, if I run a wire straight from battery post, how is the fuse box "keyed" on

 

[70_Steve]

if I run a wire straight from battery post, how is the fuse box "keyed" on

Uuhhh..... It's not! But you could make it key switched. Add a relay between the power source and the fuse box. Trigger the relay from wire 904 (Green w/red stripe, that goes to the voltage regulator)

 

[NJB71]

ty....sounds like some weekend fun

 

[Steve83]

...or add the relay AFTER the fuse box. That's how Ford does it - it puts less load on the ig.sw. & the relay. You can find fuse/relay boxes in the JY & rewire them to do exactly what you need, like this:

 

[NJB71]

TY Steve83

 

[surfer-b]

You are going to have rewire the charging system, even if you use a relay as mentioned or pull straight from the battery post. The reason being is the charge system comes from the alternator, goes through the harness, so the amp gage will work, then to the battery. So unless you rewire, as everyone should, you will be pulling the current all the way through the factory harness which is only 10 gage. You could just hook to the charge terminal on the alt and add a inline fuse but I would go ahead and do a rewire. Do a search on here about alternator rewireing you will see what I'm talking about.

 

[Steve83]

You are going to have rewire the charging system, even if you use a relay as mentioned or pull straight from the battery post. The reason being is the charge system comes from the alternator, goes through the harness, so the amp gage will work, then to the battery. So unless you rewire, as everyone should, you will be pulling the current all the way through the factory harness which is only 10 gage.

No, that's not an issue. Any load applied to the battery post puts NO load on the truck's wiring. And the amp gauge will still work perfectly.

You could just hook to the charge terminal on the alt and add a inline fuse...

Now THAT is bad advice. THAT will set the truck wiring on fire, including inside the dash, and it could damage the alt. IDK what you do for a living, but I hope it's not electrical.

 

[NJB71]

Ty Steve83

 

[surfer-b]

No, that's not an issue. Any load applied to the battery post puts NO load on the truck's wiring. And the amp gauge will still work perfectly.Now THAT is bad advice. THAT will set the truck wiring on fire, including inside the dash, and it could damage the alt. IDK what you do for a living, but I hope it's not electrical.

Yes it will put a load on the charge system, how do you think that battery gets charged. If you hook a wire directly to the batt post the system will still charge, which goes all the way through the harness. If it would not put a load on the harness then disconnect the battery from the harness and see how long it will work. All the battery is for is to start the vehicle and store temp. power its not meant to run the electrical system thats what the alt is for.

 

[Steve83]

When does your ASE for Electrical expire? How many Ford electrical courses have you passed? How many vehicles have you totally rewired?

The battery supplies the vehicle power; the alt recharges the battery continuously while the engine is running, so it APPEARS to supply those loads. But if you have a 60A alt, and you apply 100A of load, that current comes from the BATTERY. The alt still only puts out 60A, so there's NO "additional" load on the charging system or its wiring. That "additional" load only goes from the batt, thru the new wiring & back to the batt - NOT on the truck's original wiring.

And if you connect a new 100A load at the alternator, the current will come thru the charging wire (thru the dash) from the BATTERY, which could set the dash on fire. I've had to repair entire wiring harnesses from people doing things like you're recommending.

Please stop giving electrical advice. If you're a top transmission rebuilder, post away because I know squat about them.

 

[Viperwolf1]

When does your ASE for Electrical expire? How many Ford electrical courses have you passed? How many vehicles have you totally rewired?

The battery supplies the vehicle power; the alt recharges the battery continuously while the engine is running, so it APPEARS to supply those loads. But if you have a 60A alt, and you apply 100A of load, that current comes from the BATTERY. The alt still only puts out 60A, so there's NO "additional" load on the charging system or its wiring. That "additional" load only goes from the batt, thru the new wiring & back to the batt - NOT on the truck's original wiring.

And if you connect a new 100A load at the alternator, the current will come thru the charging wire (thru the dash) from the BATTERY, which could set the dash on fire. I've had to repair entire wiring harnesses from people doing things like you're recommending.

Please stop giving electrical advice. If you're a top transmission rebuilder, post away because I know squat about them.

That's quite an abrasive post. Are you here to help or just abuse people?

 

[Steve83]

Yes, it's abrasive (less so IMO than his) & assertive. No, it's no abusive or even rude. It's informative & on-topic (unlike yours & this one), and it reiterates the points I made earlier.

Would you prefer for people to think his advice was good, and follow it when we both know it's dangerous? How 'abusive' would THAT be?

 

[rob wilson]

Got to agree with Steve here. Connecting to the Bat draws from the Bat and that is all. The changing system can only output it's rated max and that's it so if you exceed that, you risk eventually killing the battery.