Checking The Wiring And Connectors

Fig 1: Identifying Ignition OFF

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Ignition off
Check the connector pin for the horn's relay in Central electronic module (CEM) #G18 (#18) for short-circuiting to voltage. Also check the cable between Central electronic module (CEM) #G18 (#18) and horn relay (2/17) in the front fuse box. Check for a short-circuit to supply voltage.
Click the VCT2000 symbol to read out relay status.
If no problem was detected, replace the relay 2/17.
Other information
Fig 2: Identifying VCT2000 Diagnostic Tool Symbol In VIDA
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