2005 Mercedes-Benz C180 (W203) — Repair Solution

1.8L M271.946 4cyl 16v DOHC VVT Supercharged MPFI Petrol Auto · Warning Light / Electrical Malfunction · Electrical

Mercedes-Benz C180 (W203) Warning Light / Electrical Malfunction Electrical Diagnostic Sequence Available

Vehicle Details

Make: Mercedes-Benz
Model: C180 (W203)
Year: 2005
Engine: 1.8L M271.946 4cyl 16v DOHC VVT Supercharged MPFI Petrol Auto
Kilometres: 123,456
Area: Electrical
Category: Warning Light / Electrical Malfunction

Customer Complaint

A warning message displayed on the dashboard stating “battery alternator.”

Problem Summary

The customer reported a “battery alternator” warning despite the vehicle starting and charging correctly. Diagnostic tests showed that the alternator was functioning and charging at 14.4V. However, a communication fault persisted between the alternator and the engine control module (ECM).

Diagnostic Sequence

The step-by-step diagnostic process used to identify this fault is available to TaT members.

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Fault Description

The detailed fault description and root cause analysis for this 2005 Mercedes-Benz C180 (W203) is available to TaT members.

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Verified Repair Solution

The confirmed repair procedure for this 2005 Mercedes-Benz C180 (W203) is available to TaT members. Includes the verified fix and technician tips.

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Quick Facts

CodeMERW205436
Vehicle2005 Mercedes-Benz C180 (W203)
Engine1.8L M271.946 4cyl 16v DOHC VVT Supercharged MPFI Petrol Auto
ComplaintVisible
Diag. SequenceMembers Only
SolutionMembers Only

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