I'm sure this question has been asked many times but I am a new member so I am going to ask it again. I purchashed a 03 E320 with 41,000 miles 18 months ago. It currently has 46,000 miles. The carrides great and looks great, however, the "Malfunction ConsumersSwitched Off" message continues to appear most of the time I drive the car. Everything works fineexcept the remote window/sunroof feature.MB dealer said the problem will correct itselfas I drive longer distances more frequently but this has been a problem for about a year. Irecently attempted to purchase a new battery but MB roadside said the consumersbattery was still ok.Will I ever be able to drive this car without looking at a malfunction warning? Anyadvice willbe appreciated.

 

Not 100% sure on E Class but the C button on the fascia (press 3 secs or so) will TEMPORARILY remove the warning.

However if the warning has been appearing for some time something is wrong.
This warning appears when the load on the battery exceeds supply and is an automatic device whereby consumers are turned off with the least important first to reduce potential load.

My first thoughts would have been that the battery was near the end of its life but this has been going on for a year (including the winter) so I suspect that even if the battery is "weak" it is not the root cause.

Get the charging circuit and battery tested. Can do this yourself with a voltmeter.

Engine off. No load. Voltage at battery??
Engine off Headlamps on. Voltage at battery?
Engine on. No load. Idle. Voltage at battery?
Engine on. Headlamps on. Idle. Voltage at battery?
Engine on. Headlamps on. 2000 rpm. Voltage at battery?

Measure these parameters and the fault should become evident.

I suspect a poor charging circuit. i.e. Alternator brush / regulatpr failure.

Advise results.

Stuart

 

Thanks for the advice. Will let you know outcome.