Adding USB and 12v Cig outlet

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dudmleh522

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Hey guys on my 2018 SCREW with 802A, I am planning to add a USB and 12v outlet on top of the center dash (behind my built right phone mount)
I am thinking of using a add a circuit and tap it into passenger side fuse box.
I want this to be on al the time hoping to use a constant power. Any suggestion on which fuse to tap into? and which fuse amp should I be using for the project?

By the way I am already using 36 for my ham radio.

Passenger compartment​

Ford-F-150-2015-2018-.._20180428140205407-1.jpg


Amp RatingProtected components
110ADemand lamp relay. Power seats relay. Glove box. Vanity lamps. Overhead console. Dome. Courtesy. Map lamps.
27.5AMemory module logic. Memory seat switches. Lumbar motor.
320ADriver door lock motor.
45ATrailer brake control.
520ANot used.
610ANot used.
710ANot used.
810ANot used.
910ANot used.
105ANot used (spare).
115ACombined sensor module.
127.5 AClimate head module. Smart datalink converter.
137.5 ACluster. SCCM.
1410ABrake.
1510ASmart datalink converter.
1615ATailgate release.
175AHUD.
185AIgnition switch and passive-entry passive-start start stop switch. Key inhibit solenoid.
197.5 ATow haul (O/D) cancel for floor or column shifter.
207.5 ANot used.
215AHUD. In car temperature with humidity sensor.
225AEPB. Power seat.
2310APDRG switch. Inverter. Driver side window. Moonroof. Vista roof.
2420ACentral lock/unlock.
2530ADriver door control module.
2630APassenger door control module.
2730AVista roof. Moonroof.
2820ANot used.
2930ANot used.
3030ANot used.
3115AAdjustable pedal switch and motor.
3210AMulti-function display. Global position system. Sync 1. Sync 2. Radio frequency receiver.
3320ARadio.
3430ARun-start relay.
355ARestraints module.
3615A360 camera module. Heated steering wheel module. Rear-view mirror. Rear heated seats.
3720APower distribution box run-start fuses.
3830A Circuit breaker.Rear window switches and motors.
 
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JAndreF321

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I'm planning on doing this today or tomorrow also. You figure it out? I'm using 36 for an ignition signal for my dual battery so that is out. Are 28-30 under ignition only?
 

FordTechOne

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I would advise against any add-a-fuse products. The fuses, terminals, and circuits in the BCM are only designed to support the load of the factory components. The add-a-fuse draws from the same source, which can result in the total draw exceeding the nominal rating. Not only that, but modules are very susceptible to voltage variances, so fuses powering modules should never be tapped into.
 

JAndreF321

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I would advise against any add-a-fuse products. The fuses, terminals, and circuits in the BCM are only designed to support the load of the factory components. The add-a-fuse draws from the same source, which can result in the total draw exceeding the nominal rating. Not only that, but modules are very susceptible to voltage variances, so fuses powering modules should never be tapped into.
Thanks for the feedback. You think that it's also bad for signal wires running to relays or DC-DC chargers? I usually see people do inline taps off of ignition-on wires so I thought fuse taps wouldn't be an issue. I'd rather not run a wire from the alternator...not even sure how that would work without looking at it.
 

FordTechOne

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Thanks for the feedback. You think that it's also bad for signal wires running to relays or DC-DC chargers? I usually see people do inline taps off of ignition-on wires so I thought fuse taps wouldn't be an issue. I'd rather not run a wire from the alternator...not even sure how that would work without looking at it.
The safest method to use a signal wire is to splice into it with a solid state relay, so there is no added load on the factory circuit. But that of course is dependent on the type of circuit, the installers’s skills, and where the splice is added. Personally I don’t recommend splicing into any factory circuits, I’ve seen too many issues caused by electrical modifications.

As far as the circuits from the ignition switch, they do not carry a load; nothing should be added to them. Like the majority of switches, they are used to provide a signal, not power any components.
 
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