E53 battery light
I have a 2006 X5. About six months ago it would not start. I checked battery voltage and it showed 11.2 volts. I replaced the battery but the vehicle still would not start. It turned out to be a fuel pump relay. After replacing the relay the vehicle fired up fine but it then displayed a battery light. I tested the voltage at the jump lug in the engine compartment it showed 13v with engine off and 14v running. Everyone kept saying it was the alternator so I broke down and replaced the alternator. The light still was intermittently on. I thought maybe I got a bad alternator so I returned the one I just put in and got another one, just to be sure. Same problem. I read another post that recommended changing the ignition switch so I did that. Problem persists. I checked the ground and positive connections. All appeared clean but I cleaned them anyway. I have looked at the plug on the alternator at least twice when I replaced the alternator. It appears clean, dry and in good condition. I disconnected the low oil warning plug, same problem. I have changed the battery a second time because someone told me that it should not have an AGM battery in it. By the way, that is what started the problem. I show 13.1 volts on the cluster when I check the voltage in the diagnostics. 13.9 when I check it at the jump start lug with the engine running while the light is on.
The problem appears to have a thermal element to it because the light won't come on when the car is cold. The warmer it has gotten over the summer the more frequent the light is on. There have been a couple of really cool mornings and the light stays off for several minutes. If I had to guess I would bet the light comes on less and less when winter returns. I'm thinking it might be the instrument cluster but i'm really hoping it is not.
I can't find anywhere at what voltage the light should come on. If it is supposed to com on at <13v then I will assume the instrument cluster is bad but I think I have to bring it to the dealer to replace the cluster so the mileage does not show tamper.
CAN ANYONE HELP ME ON THIS?????