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Old Sep 5, 2016 | 08:33 PM
  #1  
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Smart Juncton box

Not getting much response in the 6.4 forum. Maybe there are more electrical people here.

All my door locks stopped working in my 2008 F250 Crew Fx4. Locks do not work from driver or pass. door, key fob, or door keyless pad. When you hit any of the switches you can hear a relay type sound in the SJB.

There was some sort of failure because we could smell it. But I am not sure if it was the SJB that failed or a wire between the SJB and the lock motors.

Does anyone have a wiring diagram for the door lock circuit? And/or know how to troubleshoot to find the bad wire or if it is the SJB that failed.
 
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Old Oct 7, 2016 | 09:04 PM
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Door locks

Hello having the exact same problem same. What did you do about it? Same clicking sound. And I know I had a smell. Does you radio turn on when you click the button to many times when the truck is off?
 

Last edited by Parklife1977; Oct 7, 2016 at 09:08 PM. Reason: Other message
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Old Oct 8, 2016 | 08:10 AM
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I would check the switch in the door. If they get water in the switch from condensation they will short out. Look for a burnt connector also.
 
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Old Oct 8, 2016 | 10:04 AM
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I checked both switches and conectors last night. Everything appears to be normal. I also checked the wiring between the doors and the "A" and "B" posts, in the door sills, again everything appears to be normal.

Just like with mich800 I smelled something strange but thought it might be something outside when it happened but smelled electrical burning. Right after that I discovered the door locks stopped working. So my issue is the door locks do not work no matter if I use the key fob, door switches or keyless entry pad.

When the truck is off you can here a light click in the SJB. If you press the door unlock button fast enough while the truck is off the radio comes on, and while the radio is on if you pull up on the window switch the doors unlock, but if you push down the window rolls down (but you have to be pushing the unlock button simultaneously).

I have fords diagnostic flow chart written in fordinese. That really netted me nothing except going back to the SJB.
 
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Old Oct 8, 2016 | 11:04 AM
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Here is 1 of 2
 
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Old Oct 8, 2016 | 11:06 AM
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Here is 2 of 2
 
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Old Mar 28, 2017 | 04:23 PM
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parklife1977

Originally Posted by mich800
Not getting much response in the 6.4 forum. Maybe there are more electrical people here.

All my door locks stopped working in my 2008 F250 Crew Fx4. Locks do not work from driver or pass. door, key fob, or door keyless pad. When you hit any of the switches you can hear a relay type sound in the SJB.

There was some sort of failure because we could smell it. But I am not sure if it was the SJB that failed or a wire between the SJB and the lock motors.

Does anyone have a wiring diagram for the door lock circuit? And/or know how to troubleshoot to find the bad wire or if it is the SJB that failed.
Mich800 have you fixed the problem, just took mine to ford today. They tried to replace the SJB and did the same thing. Did you ever find the issue and if so what was it?
 
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