Relay and fuse box

Wiring test and functional test of an automotive cable harness and integrated relay and fuse box with a WK 260 PC test device

Testing requirements

An automotive supplier produces complete cable harnesses with integrated relays and fuse boxes. Depending on customers’ choices regarding equipment the electrical system itself as well as the relay and fuse box span a huge number of variants. Every individual unit differs through ordered options like sliding roof, seats, infotainment system and needs to be tested individually but in the given cycle times.

During the continuity test and the functional test all connections and relays need to be tested. At the same time it’s mandatory for both testing procedures to activate those relays.


The plugs of the cable harness are adapted with the adaption modules on the testing table. The electrical contact is made through spring contact probes.

The tested cable harness is than identified by using a barcode scanner and the respective data from the company’s own ERP* system is transferred to the IVISion Studio Programming and Testing Software. The individual test program is created from the loaded data and started automatically. During the test all relays are activated and connections of all wires are tested for continuity and short.

After completion of the test procedure the required protocols are recorded and archived. In case of failure, repair instructions are created. For units rated with "PASS" a label to be attached to the cable harness is printed.


Because of the integrated relays the wires of the harness can’t be tested without the activation of the relays. The WK 260 PC Test Device from WEETECH is particularly suitable for this task because it has the option to apply external voltages to the switching matrix. No additional device to activate the relays is necessary.

The WK 260 PC Test Device was chosen by the customer because of its high flexibility and the option to apply external voltages. This way, it was possible to define the setup of this testing facility more simplified, avoiding additional costs.

*ERP = Enterprise Resource Planning