Information On Insulation Fault Finding
Information
Observe the following specifications for all work described:
- country-specific, national, legal and official regulations,
- local restrictions and export restrictions,
- manufacturer's specifications from component and vehicle manufacturers,
- component-specific specifications.
These strict specifications apply in particular:
- Storage, installation and removal, transport and disposal of vehicles, assemblies, operating materials and auxiliary materials,
- handling of defective and potentially hazardous vehicles as well as assemblies,
- handling of battery electric vehicles and high-voltage components.
For this purpose, take into account relevant and qualified information sources such as local authorities, responsible importers, associations and specialist website. Deliver items to be disposed of only to authorised reception points.
Information
Insulation fault finding must only be performed if an active or passive insulation fault appears in the fault memory or in the vehicle analysis log.
- The measurements must be performed using > 9900 - PIWIS Tester 3 and a > VAS 6558A - high-voltage testing module .
- A measuring voltage of 1000 V must be selected.
- To obtain the required measuring resistance, the measuring voltage must be present on the insulation tester until a stable measured value is displayed.
- Four measurements must always be performed for each measuring point. Positive terminal on shield, negative terminal on shield, shield on positive terminal and shield on negative terminal.
- A measurement is only regarded as being within the setpoint value range if all four measured values (positive terminal on shielding and negative terminal on shielding) are within the specified range.
- The measured values must be documented in the "Insulation fault finding test log".
- The test log is stored under Repair group 2X00IN in the Service Information.
- The measurement process must be repeated after replacing a component in the high-voltage system.
Each insulation measurement must be performed four times because semiconductors and diodes are installed in the high-voltage system.
High-voltage positive to shielding and high-voltage negative to shielding.
Measurements 1 and 2 (high-voltage positive on shielding and high-voltage negative on shielding (shown as an example))
Shielding to high-voltage positive and shielding to high-voltage negative.
Measurements 3 and 4 (high-voltage positive on shielding and high-voltage negative on shielding (shown as an example))
Insulation fault finding
| 2 | E-box |
| 3 | High-voltage distributor |
| 4 | High-voltage charger |
| 5 | Voltage converter |
| 6 | Air-conditioning compressor |
| 7 | Interior heater |
| 8 | Front power electronics |
| 9 | Electric drive motor |
| 10 | Rear power electronics |
| 11 | Elect. machine |
Information
- The sequence of the measurements must always be observed .
- Fault finding is based on systematic elimination .
- Measurement must always be started from the beginning .
- The topology of insulation fault finding must also be used for better understanding of the measurements .
Information
If you are measuring a new component, absence of electric charge must be verified again (restart the Tester procedure "Insulation measurement" - First step)