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.
2021 Mercedes Benz GLC300 BaseFACTORY OEM SERVICE PROCEDURE
Electrical System - Engine - 253 Chassis
- General Information
- Basic Knowledge
- Testing & Repair
- Remove/Install Camshaft Hall Sensor - AR15.10-P-2000MRA
- Remove Install Crankshaft Pulse Ring
- Remove/Install Ignition Coils
- Remove/Install Crankshaft Hall Sensor
- Remove/Install Knock Sensors
- Disconnect/Connect Engine Wiring Harness To Remove Cylinder Head Cover
- Disconnect/Connect Engine Wiring Harness To Remove Engine
- Disconnecting And Connecting Harness At Starter - AR15.30-P-7100-03LWA
- Remove/Install Starter
- Check Regulator And Alternator - AR15.40-P-5000CW
- Check Belt-Driven Starter-Alternator - AR15.40-P-5002MRI
- Test Alternator Charging Current - AR15.40-P-5011CW
- Alternator Tightening Procedure - AR15.40-P-5032-03MR
- Remove/Install Alternator
- Tightening Procedure For Belt-Driven Starter-Alternator - AR15.40-P-5060-01MRH
- Remove/Install Belt-Driven Starter-Alternator - AR15.40-P-5060MRI
- Remove/Install Alternator Belt Pulley - AR15.40-P-5710LWA
- Remove/Install Regulator For Alternator - AR15.40-P-5760LWA
- Test Alternator Diodes - AR15.40-P-9301-02CW
- Remove/Install Coolant Temperature Sensor
- Test & Adjustment Values
- Maintenance
- Torque Specifications
- Wiring Diagrams
- Wiring Diagram Of Starter, Alternator, Battery
- Wiring Diagram Of Starter, Alternator, Battery - PE15.00-P-2101-97FBB
- Wiring Diagram Of Starter, Alternator, Battery - PE15.00-P-2101-97FCC
- Wiring Diagram Of Starter, Alternator, Battery - PE15.00-P-2101-97FCD
- Wiring Diagram Of Starter, Alternator, Battery - PE15.00-P-2101FBB
- Wiring Diagram Of Starter, Alternator, Battery - PE15.00-P-2101FCC
- Wiring Diagram Of Starter, Alternator, Battery - PE15.00-P-2101FCD
- Wiring Diagram For Engine Start/Stop
- Wiring Diagram Of Starter, Alternator, Battery
- Special Tools
Factory Service Tools
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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