Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Auto Start
When the driver is to pull away, he/she depresses the clutch pedal, shifts the gear lever into a gear and releases the clutch pedal. The system requests autostart of the engine.
- The clutch pedal is depressed.
- The secondary battery relay (2) is activated and the contacts close.
- The secondary battery (1) is connected.
- The battery relay (main battery) (4) is activated and the contacts open. Only the starter motor's circuit is now connected to the battery (main battery).
- The vehicle is powered from the secondary battery (1).
- The starter motor relays (5) are activated and the contacts closed. The starter motor's solenoid switches on and the starter motor starts.
- The battery diode (3) ensures electrical system supply in this mode if the secondary battery for any reason cannot supply the electrical system due to wiring fault or poor battery performance.
- When the engine has been started, the relays return to their normal positions.
- If the secondary battery requires charging, the secondary battery relay (2) continues to be active for some time.
In the event of an unintentional stall, i.e. an autostart fails and the engine stops, shift the gear lever into neutral and depress the clutch pedal again to reactivate autostart, follow the instructions in the Driver Information Module (DIM).
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.