Test Alternator Diodes - AR15.40-P-9301-02MFD
Engine 260 in model 118, 177, 247
Engine 282 in model 118, 177, 247
except code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN))
| Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running. | Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts. | AS00.00-Z-0005-01A | |
| Notes on safety-relevant components | AH00.00-Z-0019-01A |
Shown on model 177 with engine 608
- Connect engine tester with oscilloscope (030).
- Start engine.
- Switch on low beams.
- Assess diode harmonic content at 3, 000 rpm (engine speed).
It is not possible in this test to assess the exciter diodes.
- Switch off low beams.
- Switch off engine.
- Disconnect engine tester with oscilloscope (030).
An example: Harmonics, if diodes are OK (peak stresses possible but of no significance)
Example: Harmonics when a positive diode is defective (example)
Example: Harmonics when a negative diode is defective (example)