robertelee

hi everyone hi, i have a mercedes e320 cdi 2003. i have seen a few threads that are similar but i think mine might be skightly different. last month i started seeing battery protection, convenience functions not available. then one time my battery was totally dead. so when i checked i found that the battery was too small so i bought the spec battery(it is a beast!).

no probs for a while but now when i drive it will suddenly say battery protection etc out of the blue etc for a couple of minutes then go away. so far it is fine when i start it up....touch wood. When the sign is on the ac doesnt work and neither does the passenger chair but everything else is fine.

if it was the battery then surely it wouldnt be able to start? plus it is brand new so i dont see how it could fail. And why would it suddenly come on after driving for 5 mins or so.

any help would be greatly appreciated

thanks

mohd.awaly

Since you changed the battery so It might be the alternator then my freind .. when the engine is on voltage should be somewhere between 13.5 and 14.5 volts , if it gets lower than that you will get that message ...

drgeeforce

Take the alternator in to get the voltage regulator checked, I doubt it is a spinning problem since you have a serpentine belt and tensioner. Some of the older CDIs with v-belts may be too loose not spinning the alternator enough.