Citroen C4 - Faulty battery condition detection

In the above-mentioned vehicle type, a warning message relating to battery charging may appear on the instrument cluster even though the alternator is working properly and no restrictions can be identified in the vehicle electrical system or when starting the engine. If the above-mentioned fault applies and no definite faults have been identified in the periphery of the affected systems during troubleshooting, pay particular attention to the vehicle electrical system battery monitoring sensor, which has been integrated into the ground wire at the negative terminal.

This sensor continuously records parameters including voltage, current flow and temperature of the vehicle electrical system battery and sends these to the superordinate control unit for energy management. If there are faults within the sensor – for example due to internal electronics faults or faulty signal processing – this may result in implausible measured values. As a result, the control unit interprets the data as a critical state of charge, even though there is actually no lack in electricity supply, and generates a corresponding warning message on the display.

For troubleshooting, check the vehicle electrical system battery monitoring sensor parameters using a suitable diagnostic device. In this process, check for plausible values and comprehensible signal curves. If you identify values that do not correspond to the current load state or if they remain unchanged, initially check plug connections for corrosion, damage or contact issues. If you are unable to identify abnormalities here, replacing the sensor as per the manufacturer's instructions may eliminate the issue.

Once the cause of the fault has been rectified, delete the fault memory and then go for a test drive.

Reprinting, distribution, reproduction, exploitation in any form whatsoever or disclosure of the contents of this document, even in part, is prohibited unless our express permission has been obtained in writing beforehand and the source is stated. The schematic illustrations, pictures and descriptions are provided for explanatory purposes and are only intended as a visual supplement to the document text, so they cannot be used as the basis for installation or assembly work. All rights reserved.