E650 - Supply voltage too high airbag control unit fault

What does error code E650 mean in the airbag control unit?

Error code E650 reports that the supply voltage of the airbag control unit is too high, that is, not within the intended voltage range. The control unit stores this fault in the fault memory and switches on the airbag warning light, so that the condition becomes visible in the vehicle and can be read out later.

The supply voltage is the voltage with which the control unit is powered. If it is too high, the control unit reports exactly this condition.

The airbag control unit is part of the restraint system (SRS), and its power supply is the affected area.

How do you recognise error code E650?

The airbag warning light stays lit permanently, not just briefly when the ignition is switched on, and the code is stored as an entry in the fault memory of the airbag control unit. It cannot be permanently cleared, and it is read out with a diagnostic tool that specifically queries the control unit's fault memory.

The visible sign is the light on the dashboard. Whether the code is actually stored only becomes clear when the fault memory is read out.

What causes error code E650?

For this code, the causes are mainly the power supply of the control unit, connectors and wiring, and the control unit itself, although the cause must be checked in each individual case. Possible causes include voltage spikes from a weak battery or a jump start, and ageing electronic components in the control unit are also possible.

• The voltage on the vehicle electrical system is too high and reaches the control unit.
• Moisture or corrosion has formed on the connector of the power supply.
• Wiring of the power supply is damaged or has a contact fault.
• The control unit itself is operating incorrectly internally.

Which of these causes applies is only shown by testing at a specialist workshop.

In which vehicles does error code E650 occur?

Based on the information available, this code is known on Citroën vehicles, namely the C3 Aircross III, C3 Picasso I, C4 Aircross I, C4 Cactus I, C5 Aircross II and ë-C3 IV models. On other vehicles the meaning may differ, and the list is not complete.

Only the models on which the code is known so far are named here. Other Citroën vehicles are therefore not ruled out.

How is error code E650 resolved?

Error code E650 is resolved by first having the fault memory read out with a diagnostic tool and narrowing down the cause. If the cause lies in the connector, wiring or power supply, the affected point is first checked by a specialist workshop; if it lies in the control unit, the unit is sent to our workshop in Berlin for repair.

Work on the airbag system should be left to qualified professionals. Therefore, first have the fault memory read out with a diagnostic tool, and if the connectors, wiring or power supply are a possible cause, have these checked by a specialist workshop first.

If the cause lies in the control unit, first disconnect the battery and then remove the control unit. Then create a repair order online and send the unit to our workshop in Berlin. Checking, repairing and testing usually take 3–4 working days.

The repaired control unit comes back with all vehicle data and is ready for use as soon as it is refitted — no coding or programming is required.