1. Disconnect from the electronic unit located under the brake master cylinder (v6 engine), connector and perform the following checks, referring to the diagram (see subsection 12.2.2.)
2. Check for battery voltage at terminal 9 of the connector.
3. Check for 5 V voltage on pin 4 of the connector. If there is no voltage, then send the processor unit for repair.
4. Check for fluctuating voltage of 0.1-4.5 V on pins 5, 6 and 7 of the connector (to do this, ask an assistant to turn on the starter). If there is no voltage, then take the processor unit for repair.
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5. Check the reliability of the ground connection of terminal 3.
6. If the tests are positive, disconnect the connectors on each coil and check for a signal using the LED (see subsection 3.4.5.). If there is a signal, then check the integrity of the circuit from the ignition unit to the coil. If the circuit is in good order, then replace the ignition unit.