2005 XJ8; last week strange behaviour of wipers creeping up the glass when wipers not activated; then random warning lights, all suggesting to me a failing battery. New battery installed at battery shop, OBDII port used to maintain radio codes. Different warning lights: suspension, parking brake, cruise not available etc and finally CEL.
A hard reset was done but warning lights still show and wipers still creep. My assumption is that the new battery is not fully charged so it will go on the CTEK unit until it is charged with the hope that all will then be well. But may I have an informed option on all this, especially regarding the warning lights? If the battery was and is the issue will the CEL extinguish immediately or will it take several run cycles to clear?
Opinions gratefully received.

 

Would make sense to read the codes.

 

Read the codes and check earths behind headlights.

 

Thanks to both for the suggestion about the codes. I cannot check the codes yet because the car is not at home at present; undoubtedly many codes will show, given the different system warning lights that have been presented. But common sense and experience tells me that regardless of the codes, there is a common electrical cause to the problem, and that is what I am after: a faulty ground connection in all probability (and the grounds near the headlamps will be checked and cleaned -thanks for that), but a similar thread blamed the same series of symptoms on an unlikely candidate: the J-gate unit connector. Happily, I have an good extra unit that I will substitute within the week, and I will report if it makes a difference.

 

Well, my original thought regarding all these random warning lights was that the battery needed replacement. So it was replaced. The warning lights (variable and varied) remained: ABS, park brake, cruise not available, CEL, etc. And the wipers would creep up the screen.
My next thought: this has to be a bad ground connection. And it was. The connections in the trunk were clean, tight and dry. Next, the grounds behind the headlamps: they were not loose but they did not look particularly healthy. So I removed them, cleaned them up, refitted tightly. Result? A half hour drive showed no warning lights at all, the wipers stayed properly parked and the big Jag (XJ8 VDP 4.2) ran perfectly. Further use will prove whether or not this is the complete cure but signs are good. What I do not know is which modules are grounded at those two points.