Originally posted by DR.DIESEL
Part of the problem may be in the idle control system.
If the car is idling very low and cannot get the alternator
spinning fast enough to get voltage above 11volts, you will
get the battery charge warning message.
I have also seen several alternator failures on 98/99 E300D's
lately. The average milage has been around 75K for failures.
I would have FJMB keep it overnight and cold start it the following morning with test equipment attached to monitor alternator output, voltage, and idle speed.
Thanks for the ideas Dr. Diesel.
The idle has been the same at about 700 rpm for the last 7,500 miles since I first acquired the car.
I thought that the problem might be because the motor was not revving up high enough also, so I had tried increasing the rpms up over 2000 rpms, but it still would drop the load until after it had warmed up to normal operating temperatures.
Four mornings in a row it did this "Battery-Charge" message drill until the motor was up to normal operating temperatures, and then everything was alright for the remainder of the day.
But yesterday morning and again this morning, there was no problem although it was colder this morning then any of the previous mornings.
I postponed that diagnotic appointment for today until next Wednesday because I couldn't see taking the car the more than 65 miles from Murrieta to FJNB in Newport Beach today to have them not be able to replicate the problem as it had been occurring in Las Vegas and here in So Cal.
Perhaps the problem will reappear?
When the car was checked out Monday in Las Vegas, FJNB reported: "check charging sys & battery condition. Check key off draw - 40 mamps. Found pos batt terminal loose - resecured."
Tech: 324 Daimonji, Derek
BTW, the car just rolled 90K, so if
it has not ever had a new altenator, it surely won't be long, will it?