I cannot figure out what’s wrong with my car. These three error messages just do not go away. I checked the EBM and it’s not even there. Or at least it’s not where it’s supposed to be
I see the screws where the module was bolted in but no module. I hear it can be a battery problem I tried to get it tested for the volts but it’s asking for type of battery, but the battery in the car has no info on it. Also the parking brake works and disengages when I put it into drive.

 

put a good used battery in

 

Looks like a fairly common XJ battery problem. First step is to confirm it's not the battery. Remove the battery and get it fully charged and load tested. If it can hold a full charge, put it back in the car and these issues may well go away. I've had very similar symptoms in the past it it was a dead cell in an older battery that couldn't hold a full charge. Once I replaced the bad battery the problems went away.

Good luck with it.

 

In my case a similar problem started due to a bad battery, but the problem was still there after the old battery was replaced, finally when I replaced the ABS Wheel Speed sensor everything back to normal. It was the one located on my rear right wheel. It was a very easy one to replace.

 

My 05 XJR does this also. It usually manifests as; the cruise control goes inop, all the lights in the dash panel flash, the gauges go to zero, then a parade of faults cross the info panel (transmission, park brake, ETC) It might do it several times in a day, and then not for 6mo. Replacing the fuel cap was promising, but then it did it 3 times a week later. I wonder about the little chip they sell with the coil-over suspension kit. I see your SDD making note of ride level control not communicative. I think mine is behind the rear seat, the conversion was done before I got it, so I'll just have to find it. I sure hope someone finds a common cure for this, it is more annoying than anything, the car doesn't go into limp home mode, it does set the CEL, but that usually goes away on its own. You can clear it, but it seems to be better just to let it clear itself. My battery is about a year old, a premium brand, and nothing else seems to lag or drag, to indicate low voltage.