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Smart Junction Box Blues

36K views 14 replies 10 participants last post by  jbd55 
#1 ·
Hey everyone,
It's been awhile since I've been on this. I had and still do have a problem with my smart junction box. It all started with one right rear tail light wouldn't work, then the other right tail light went out. Both wires coming back to the lights from the junction box are dead. The right front turn light works fine. Anyway I want and need to get this problem fixed. I called Ford and they said if I replace the box myself they would code it for around $100.00. I just want it fixed because I got a sequential light system for Christmas. What do you think? Does this sound like this should fix the problem?
 
#3 ·
How much would it cost if the dealer did it?
 
#5 ·
I can get the box for 250.00 (I have taken it out before, trying to fix this problem) the dealer said they would charge 100.00 to program it. I just want to make sure they know what they are doing and that it would fix the problem.. I got concerned when the guy at the dealer asked where it was followed by to the left of the steering wheel :?:
 
#7 ·
The dealer tech can actually connect up their VCM (vehicle communication module) and get specific DTC's from the SJB that should identify if the SJB has failed.

Just out of curiosity did you check connector C411 and ground G402? This connector and ground is under the rear plastic trim panel in the back of the trunk to the right of the trunk latch. You say the right rear tail light it dead? Are none of the lights in it working? Turn, flasher or running? How about the right rear side lamp?

Just trying to help you cover all the bases before you got to lay out out for a new SJB.

If it needs replaced the dealer tech needs to upload the data from your old SJB, it holds the anti theft, keyless entry data and communicates with the PCM. Once the new SJB is installed then the data needs to be downloaded to it.

This is only an educated guess but I bet if you install an SJB from a salvage yard the car won't start because of the anit-theft. I might be wrong on that one though.

One other thing. If you have to have yours replaced I would be willing to buy your failed one. PM me if your interested:bigthumbsup
 
#8 ·
Thanks for the responses. I did check the ground under the panel. It seems to be fine.. I do have marker lights. All three light up and the side marker lights up. I do not have turn or brake lights on the right side. But I did jump one bulb from the third brake light so I have brake lights and then I jumped the wire for the front right light back to the other light so I have a turn light on the right side. I think I will drive over to Ford and talk to them. I agree the have to do something about down loading my box and up loading the new box.. I will let you know what I find out. If I get it working with the new box I will let you have the old box to play with.... thanks everyone for your help and if any of you find out something else please let me know....
 
#9 ·
Just a update. I ordered a smart box and it's on back order. I will let you all know what happens when I get it.
 
#10 ·
Update on Smart Junction Box Blues... I got the smart junction box (it's been on back order). I took off both battery cables. Took out the old sjb and installed the new one, hooked up the battery cables and tested out everything. The turn signals work:). The keyless remote would not operate the doors, I put the key in the igntion and turned it on and off until the doors locked and then pushed both the lock and unlock buttons on the remote and it programed the remote. But the alarm will not set. I haven't found out how to reset that yet... One other thing the headlight come on when I turn on the key.
 
#11 ·
The SJB you installed prob. has base programming, but the options need to be entered. The only way I know now that the swap is done is for the dealer to enter VIN spec. as built data. $100 may seem outrageous but it is specialized equipment with very high monthly update costs so you are paying for that. If headlights are coming on with no park lights we call that daytime running lights way up north here in Canada
 
#12 ·
Smart Junction Box

Hi everyone,

I'm not driving a GT, but my headlights were stuck on high beam even when off. I took it to the dealer and they said there was water intrusion? Anyway, they quoted me like $550 to replace it!
Unfortunatly I can't do it myself so I'm stuck having to use the dealer because of the re-code issue.
 
#14 ·
i had the same issue, but now another issue..

hey guys im starting up this thread again bc i had a guy at my local shop tell me that i need to replace my smart junction box and since i know nothing about it, i figured i would do a little bit of research! Seeing as you Aihler replaced your s i really need som feedback from you guys.

So i had the same issue with the tail ights not working on the passenger side in my 07 gt. so i checked all the fuses and one was out that was labeled SJB #4 and replaced it and they went to working. so now my ac isnt working and all my fuses are good and the guy at my local shop says the compressor isnt getting power, and checked all grounds and everything is fine, so then he called ford an they said it sounds like the SJB needs to be replaced and it could be around $300??? But reading what yall have said, someone evidentally paid $1000 for it, so im happy with the number 300 haha But guys i need help!!!
 
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