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.
Locking And Unlocking Test Functions
Only the first two test functions are freely accessible. All test functions after the third test function are locked. Unlocking can only be carried out removed by means of test function 19. In test function 19, the display switches in intervals of 1 second from L_ on to L_ off (Lock on and Lock off). The test functions are unlocked or locked by pressing the left control button (S/R for Set/Reset).
If the left control button (S/R for Set/Reset) in the instrument cluster is pressed while L_ off is displayed, the test functions remain unlocked or are unlocked. The display jumps to test function 0.
If the left control button (S/R for Set/Reset) in the instrument cluster is pressed while L_ on is displayed, the test functions remain locked or are locked. The test functions can be locked by means of test function 19.
Use the Manual With the Right Hardware
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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.
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