E-350 wiring question - tapping in to Smart Junction Box (SJB)

pugslyyy

Robinson Fuso
I'm trying to understand the wiring on my 2010 E-350. The Smart Junction Box is fully populated with fuses, but on circuits that are not used the connectors don't have pins for the unused circuits.

What is the best way to tap into and take advantage of the circuits that are prewired through the SJB?

For example, F40 is a 20amp always on circuit that goes to nowhere. The C2280A connector doesn't have anything connected to pin 8. (It is for an audio amplifier that is not present on my van)

Is there a way to add the female contacts into the connector? They are very thin female spade lugs.

 

mgmetalworks

Explorer
Yes you can use most* of the open circuits, buy the terminals on Mouser.com, crimp on a wire, snap it into the connector. I don't have the terminal part number handy but I can find it and post here.

*In the wiring diagram, some of the circuits are designated as being part of the "smart" portion of the SJB. Use the open circuits that aren't controlled by this portion of the SJB. And because the SJB is a somewhat sensitive piece of electronics (it is a computer after all), I'd use the circuits for powering the coil side of relays or small indicator lamps but I wouldn't put big loads directly on the circuits.
 

pugslyyy

Robinson Fuso
Yes you can use most* of the open circuits, buy the terminals on Mouser.com, crimp on a wire, snap it into the connector. I don't have the terminal part number handy but I can find it and post here.

*In the wiring diagram, some of the circuits are designated as being part of the "smart" portion of the SJB. Use the open circuits that aren't controlled by this portion of the SJB. And because the SJB is a somewhat sensitive piece of electronics (it is a computer after all), I'd use the circuits for powering the coil side of relays or small indicator lamps but I wouldn't put big loads directly on the circuits.
Thanks, if you can come up with the part number that would be fantastic! Microcat doesn't let me drill down below the wiring harness. :(

 

pugslyyy

Robinson Fuso
I had pretty much this same exchange with another member over on the SMB forum. Take a look at the links we we posted. Your connector and terminal information is in there. I'm pretty sure that connector is a Yazaki brand.

http://www.sportsmobileforum.com/forums/f20/2012-upfitter-switches-15026-3.html
Would you be able to educate me about the upfitter switches? I know that they activate relays in the Battery Junction Box (BJB), but I can't figure out where the wires go after that. The Ford factory wiring diagrams haven't been any help to me at all.
 

mgmetalworks

Explorer
There's a bundle of wires under the hood with some shrink tube over the ends. Just to the left of the brake booster along the top of the firewall coming out of the main harness. 4 wires corresponding to the 4 switches/relays. Once you put a relay in the BJB, those wires are hot with the switch on.

upfitter 1 is YE
upfitter 2 is GN-BN
upfitter 3 is VT-GN
upfitter 4 is BN
 

pugslyyy

Robinson Fuso
There's a bundle of wires under the hood with some shrink tube over the ends. Just to the left of the brake booster along the top of the firewall coming out of the main harness. 4 wires corresponding to the 4 switches/relays. Once you put a relay in the BJB, those wires are hot with the switch on.

upfitter 1 is YE
upfitter 2 is GN-BN
upfitter 3 is VT-GN
upfitter 4 is BN
Ah, okay - thanks!

I did see that I needed to add the 4 relays to the BJB and ordered those today.

Is it just me or is the E-series poorly documented compared to the pickups for stuff like this?
 

mgmetalworks

Explorer
Ah, okay - thanks!

I did see that I needed to add the 4 relays to the BJB and ordered those today.

Is it just me or is the E-series poorly documented compared to the pickups for stuff like this?
I think the printed wiring diagram is about as detailed as you can get. I love the Ford books compared some other manufacturers!

I have several of these manuals... http://www.ebay.com/itm/2014-Ford-E-Series-E350-Electrical-Wiring-Diagram-Manual-XL-XLT-4-6L-5-4L-V8-/252510232695?hash=item3acac86077:g:HwIAAOSwMtxXvG8h&vxp=mtr
 

pugslyyy

Robinson Fuso
I think the printed wiring diagram is about as detailed as you can get. I love the Ford books compared some other manufacturers!

I have several of these manuals... http://www.ebay.com/itm/2014-Ford-E-Series-E350-Electrical-Wiring-Diagram-Manual-XL-XLT-4-6L-5-4L-V8-/252510232695?hash=item3acac86077:g:HwIAAOSwMtxXvG8h&vxp=mtr
Good, maybe it will get simpler as I get more familiar with it then! My issue is when I see the parts of the diagram circled in red, I have no idea where to look.



Do the paper manuals have more information in them than the digital?
 
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dhally

Hammerhead
Good, maybe it will get simpler as I get more familiar with it then! My issue is when I see the parts of the diagram circled in red, I have no idea where to look.



Do the paper manuals have more information in them than the digital?
Ford has additional resources online at https://www.fleet.ford.com/truckbbas/topics/qvmp.html

There is a large Body Builder's Layout Book, and then SVE Bulletins for specific things. I found one Q-92 that shows the location of many electrical items.

Good luck!
 

Timjim

Observer
Hey,

I am Flux on the SMB board and that linked thread. MG helped me out big time with a similar issue here as I have no wiring harness for the upfitters. He's a very generous guy with his knowledge and his skill with this stuff is on a whole other level.

Those wires circled in red will be under your hood in a bundle. Blunt ends with heatshrink over them. They are the actual triggered power wires that come from the main battery junction box under the hood. If your deal is like mine, both the fuses and relays are not present in the BJB so you will have to work those out.

Basically the SMJ provides power to the Upfitter switches for illumination and triggering the relays in the BJB. The power wires switched by the relays sit under the hood.

I took MG's suggestion and bought the E-series wiring book. It's terrific and has details on every connector, except who made them of course.

I have the connectors and pins and such, hit me up for part numbers and suppliers if you need them.
 
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pugslyyy

Robinson Fuso
Hey,

I am Flux on the SMB board and that linked thread. MG helped me out big time with a similar issue here as I have no wiring harness for the upfitters. He's a very generous guy with his knowledge and his skill with this stuff is on a whole other level.

Those wires circled in red will be under your hood in a bundle. Blunt ends with heatshrink over them. They are the actual triggered power wires that come from the main battery junction box under the hood. If your deal is like mine, both the fuses and relays are not present in the BJB so you will have to work those out.

Basically the SMJ provides power to the Upfitter switches for illumination and triggering the relays in the BJB. The power wires switched by the relays sit under the hood.

I took MG's suggestion and bought the E-series wiring book. It's terrific and has details on every connector, except who made them of course.

I have the connectors and pins and such, hit me up for part numbers and suppliers if you need them.
Excellent, thanks! I added in the pin for the SJB audio amp circuit today to power my subwoofer. Slick as snot.

I couldn't figure out the correct pin for the PCM connector to pull the battery charge protect signal, so ended up hacking something (using another connector I had that seemed to work okay). Since it is a power circuit it should be okay - and if not it is not critical.

I did figure out that the relays and fuses were not present in the BJB. Snagged 6 relays off ebay for $18, but also need to get some of the 30A low profile case fuses.
 

Timjim

Observer
Very nice! Which plug/pin# did you end up using?? I'd like to add a little amp behind my Head unit and that would be excellent reference. It's kind of hard to figure out what pin is what fuse in the SMJ.
 
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