Notes on avoiding damage to ignition system - AH15.10-P-0002-01RQ
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ENGINE 159
- To avoid damage to the ME-SFI control unit, connect and disconnect the two connectors on the ME-SFI control unit only when the ignition is switched off.
- Terminal 1 of ignition coils must not be short-circuited to GND, e.g. when installing antitheft protection.
- Only install original ignition system components.
- Do not operate ignition system at starting speed unless all of the ignition cables are connected.
- Never perform 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, at cranking speed or when the engine is running.
- Every high voltage circuit must be loaded with at least 2 kΩ (spark plug connector).
- The only way to test the ignition spark when providing roadside assistance, is with a spark plug on spark plug connector. Ensure that spark plug has good contact to ground.
- Before working at cranking speed, e.g. checking compression pressure, switch off ignition and disconnect connector "2" from the ME-SFI control unit.
Use of testers and testing units
- 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.