2008 E350 5.4L Problem

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I own a 2008 Ford E350 Super Duty Econoline van. It has a 5.4L gasoline engine, and 4 spd auto trans. Problem is after start up the Wrench Limp Mode light stays on and the check engine light stays on. Truck was running fine until I disconnected the negative battery cable, and the positive was on but loose. I had to remove some outside electronic equipment (Qualcomm). I used it for expediting and it has 514,000 miles on it. (99% interstate miles). Ran fine before this work was done.

Any ideas what the problem could be?