2013 xc70 chaos after battery replacement
 

hi folks-decided to carry out a battery replacement as preventive maintainance-ahem really wish i hadnt....

changed battery for a bosch newbie-started car,reset windows which were about the only codes to come up on first scan
Took out for a drive-instant limp mode,loads dash warnings and an armful of codes,coo codes[too many to mention,comms,algorithms etc]-so i cleared these and they keep coming back
battery showing 12.4 v engine stopped 14.4 running[vida]

its not a stop start so i didnt code battery in[if you can]

any idea what has went wrong-loads strange things happen=idles at 1500 rpm,sometimes wont come out of p,tells you its not in p when it is

also any idea what the wire is that goes from positive to negative terminal-its got a thin bit to blow in case of an accident or major short i should think-looks like it has been pinched in middle a bit-could this be relevant

previous owner had issues with the car,but i havent,although there were a raft of faults logged when i bought vida they all cleared off and didnt return[except my faulty pam module]

as usual any help welcome-it must have happened tosomebody else on here before lol

did you follow the correct battery reconnection procedure? can you post a pic of this suspect wire between terminals

procedure
 

i disconected earth first on removal to replace i connected positive first

This car has a history of failure scince end feb-it was fine with me until i removed battery
The same fault codes stored were in the memory when i bought it,were easily erased then
I seem to have been able to re-create the fault/s issues by changing battery

The wire is covered in a black nylon sheath-this i removed to look at it [the sheath] and it starts off thick at positive-has a very very thin section in centre then goes to a plug on the block attached to negative terminal
cant get a pic right now as not at car-its about the only fragile looking part where battery is-looks like it might be a fuse/ current spike wire designed to blow

there is a procedure to follow when reconnecting battery key in position 2 its possible you may have spiked some of the electrical modules re scan with vida to check modules

vida
 

vida scans all the modules,clears the faults[except my faulty pam module and they all come back fairly quickly,i can drive the car maybe a mile...then it starts throwing all the warnings up
Strange
unless its a duff bosch new battery-but it starts the car,shows 12,4 v and 14.4 once running

may be this is one for clan he may reply when he spots this thread or you could pm him

issues
 

i have removed battery tray-positive feed into front fuse box feels loose-i am not sure how it terminates but will have a good look tommoz

There is also a very green looking earthing point under the lhs scuttle-now visible with the box removed-it goes to a heavy duty connector,so will remake this also after i pull the wiper arms off and remove scuttle

I did retry the original battery just in case but after refitting it seemed even a little more scatty than it was with the new one fitted-hence me checking the feed into the front fuse box[off main positive]-i need to lift the top tray and get to the lower part of the fuse/relay box-hopefully i can see whats what-the car has done this before-so hopefully more a physical fault than modular

will pm mr Clan if i get nowhere tommoz[if its dry lol]

try accessing the wiring diagram in vida clean and remake any loose or coroded connections as these can play havoc with canbus systems

I've never had issues with battery disconnection, It's always been, Negative off, Positive off, Battery out, Battery in, Positive on, Negative on. I've NEVER had any issues, regardless of any car that supposedly loses its mind everytime a battery gets disconnected. My Chrysler, Dodge, Dads 03 v70 and this '09 xc70. All of which have had batteries changed/disconnected/charged.

12.4 is a touch on the low side for a new battery in good health. May be worth a proper drop test, see how the battery responds. It's not super common, but also not unknown for new batteries to be faulty.