2010 5.7 4wd battery/ All CEL/ limp mode / no reverse

Hey all,

I read through every post I could find on here before I posted.

2010 5.7 4wd. 286k. Never had an issue out of this truck but due to the purchase of a new vehicle the tundra hasn't been used in about 3 months.

Tried to start it, battery was dead. Jump started it and let it warm up. Hooked up my trailer to haul something trash.

Drove down the road and about 5 minutes into the trip every light on the dash lit up like a Christmas tree, every CEL came on and the truck derated into limp mode.

Got it back to the house, backed it in.
Next morning put a brand new battery in it and fired it up. No lights, warnings, or CEL.

Now now the truck will not go into reverse at all. The dash indicates that it's in reverse but truck just revs like it's in neutral..


I have seen similar posts to this on this forum but the one thing I haven't seen is when I put the truck in reverse the RPMs get reduced to about 500 while applying my foot to the brake. When I let off the break and hit the gas it just revs like it's in neutral.

Any thoughts or info would be greatly appreciated. Thank you in advance