Hi. In need of help. A customer of mine has a 04 s type 4.2 V8. After driving for 7 miles the battery light came on. Rev counter stopped working. Hand brake fault, gearbox fault, asc/dsc fault all came one. He pulled over, switched off. Started up again and it cleared but left engine management light on. Drove 7 miles and same again. Plugged my snap-on solus pro in and came up with
P1637
P1638
P1699
P1260
P1582
P1799
P1774
B2141
U2523
U2522
Cleared all codes and fine for yes you guessed it (7 miles) then battery light on rev counter stops and loads of faults abs/asc gearbox ect.....
Normally battery light go's off within fue miles and rev counter works again. But with code reader plugged in when battery light comes on I loose communication with code reader. When battery light go's off I can get into codes again. This time I switch engine off when the battery light ON!!now the car won't turn over and I can't communicate with code reader. It's had new battery. New altenator. I've checked all fuse's. has anybody got any ideas. Many thanks in advance

 

Bad ground or power or some such. You even have network faults.

Normally it would be a bad battery but ...

 

I would check your harness connectors under the hood and start there I dont want to sound crazy but your battery is in correct +- crazy things do happen

 

time for new battery ??? It is known that a weak battery might cause all sorts of issues..