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Energy Diagnosis: Unfavourable Customer Usage



Energy Diagnosis: Unfavourable Customer Usage

Unfavourable customer behaviour with vehicle faults is a main cause of breakdowns due to a depleted battery. In detail, the following individual causes can be determined:

Position light, parking light or hazard warning lights were switched on
The position light, parking light or hazard warning lights were switched on for too long with the vehicle parked. If possible, point out these facts to the customer.

Terminal R or terminal 15 was switched on
Terminal R or terminal 15 were switched on for too long while the engine was off. The current consumption of the vehicle is then, depending on the equipment, 10-15 A. This discharges the battery very quickly. If possible, point out these facts to the customer.

Long immobilisation period
The vehicle was parked for a very long period. The vehicle has a standard closed-circuit current consumption of 10 - 40 mA, depending on the equipment fitted. This leads to slow but continuous battery discharge. Depending on the state of charge of the battery when the vehicle is parked, the residual capacity necessary to start the vehicle is reached after an immobilisation period of approx. 4 - 12 weeks. If possible, point out these facts to the customer.

Unfavourable driving profile
The battery can be depleted due to unfavourable driving characteristics of the customer:
- In the case of extreme short-distance driving, it is possible that starting the engine takes more energy from the battery than is charged in the subsequent trip. The charge balance deteriorates if a great many current consumers are switched on during the subsequent trip.
- Very few trips: If the vehicle is moved very infrequently and the individual trips are not sufficiently long, it is possible that during the immobilisation period more energy is taken from the battery by normal closed-circuit current than is charged while the vehicle is being driven.

If possible, point out these facts to the customer.