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.
Notes on avoiding damage to ignition system - AH15.10-P-0002-01E
ENGINE 103, 104, 119 with CFI-EΒ
- To avoid damage to control unit, only connect and disconnect the two connectors on control unit when ignition is switched off.
- Terminal 1 of ignition coils must not be short-circuited to GND, e.g. as antitheft protection.
- Only install original ignition system components.
- Do not operate ignition system at starting speed unless all of the ignition cables are connected.
- No tests such as holding ignition cable 4 at a distance to GND, unplugging a spark plug connector or pulling cable 4 out of the ignition coils, may be performed at starting speed or when the engine is running.
- Every high voltage circuit must be loaded with at least 2 kΞ© (spark-plug connector).
- If it is necessary to test the ignition spark when providing roadside assistance, this must only be done with a spark plug at a cylinder ignition cable. Ensure that spark plug has good contact to ground.
- Before working at cranking speed, e.g. checking compression pressure, switch off ignition and detach crankshaft position sensor coupling(s) from DI switching unit.
- The DI switching unit is mounted for better heat dissipation with thermal-conduction paste onto the wheel arch panel. When being replaced, the protective foil must not be removed, it does not impair the heat dissipation.
Use of testers and testing unitsΒ
- Only connect and disconnect secondary measuring sensor to corresponding ignition cables when vertical engine and ignition are switched off.
- If the short-circuit protection is operated (cylinder comparison) and the engine stays upright, it is not possible to conduct the test with this test instrument.
- Do not connect test lamp to ignition coil terminals 1 and 15.
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:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
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