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Power Windows & Radio

870 Views 6 Replies 4 Participants Last post by  wmburns
Hey guys i recently did an engine swap on my mustang and everything was working fine except for power windows and radio. I've replaced the accessory delay fuse and it did not fix the issue. Everything was working fine before the engine swap so im stumped. The odd thing is it cuts on after the car has been on for about 20 mins and works perfectly fine. Any pointers as to what the issue could be will be greatly appreciated. Thanks
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Just wondering......What Model year Mustang are we dealing with?
2005 ford mustang v6 4.0
The 2005+ Model Year has a "Smart Junction Box" at the core of the electrical distribution. The SJB is programmable and under the control of the PCM. This allows for far more flexibility with how accessories are controlled. This also allows for various battery saving safe guards to be put into place.

My guess is there's some signal that the SJB is looking for when the motor starts to enable all of the accessories. After 20 minutes the system "times out" and falls back to some default operation.

So my first suggestion is to re-check all of your work. Looking for any missed connectors. Then double check the connectors looking for bent/pushed pins. Pay special attention to any grounds.

The next suggestion is to get yourself a Ford factory service manual and go through the SJB "pin point" tests.

If interested in getting a copy for yourself I may be able to help. PM if interested.
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