Jaguar Repair: battery light indicator, car stalls, check battery

Question
The voltage meter reads 13 charging, however the battery indicator light brightens when accelerating and stays on dimly lit when idling.  Car stalls when battery disconnected

Answer
Hi Charles,
You need to put a volt meter across the battery posts and check battery voltage (12+ v) Then start the engine and set the idle at about 1500 RPM and read the volt meter. It should read 13.8 to 14.5 v. The Light is an indication the charging system is not working correctly or you have a cable connection problem either on the power side or the ground circuit.
Disconnecting the battery cable while running car destroy the diodes in the alternator if they are not already damaged. Not all alternators have the special grounding diode to protect an alternator if the cable were to come loose.
Howard