Intermediate capacitors
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A capacitor serving as an energy store and a voltage stabiliser may be fitted between HV positive and HV negative in high-voltage
components. In addition, a resistor which discharges the capacitor when the ignition is off is connected in parallel to the capacitor.
When the ignition is switched off, the capacitor on some high-voltage components is actively discharged by a switch and resistor so
that the components are completely de-energised when switched off.
Note
A capacitor is fitted in some high-voltage components to store power. It must be discharged when the system is de-
energised. You should therefore always de-energise the system according to the test plan in the vehicle diagnostic
tester as this takes the discharging times into account. The high-voltage system must only be de-energised and worked
on by qualified staff.
Additional information can be found in this SSP (refer to article “High-voltage battery 1 AX2”).
Power contactors
The power contactors open immediately if:
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Maintenance connector TW is opened.
The safety computer sends a crash signal via the data bus.
The safety computer sends a crash signal to high-voltage battery isolation igniter via the dedicated wire.
The fuse for power supply to terminal 30c of the power contactors is disconnected or faulty.
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