Oh sorry forgot about the diesel I have the 98 w210 e320 sedan no diesel. When the car starts its fine but when it gives me issues it will do one of two things a slight crank then cut off or it will turn over, start and then just cut back off. Sometimes if it really takes a while to start I get that red battery charge indicator. If by warm you mean that the car was recently driven then parked yes this is when the problem occurs usually at a cold start in the beginning of the day it starts up fine no issues.