Test ID 09 - Engine Coolant Temperature Sensor G62

Test Prerequisite 

• There must not be any DTCs stored in DTC memory → Diagnostic Mode 03 - Read DTC Memory  .

Procedure 

• Connect diagnostic tester → Diagnostic Tester, Connecting .
• Perform a road test until a coolant temperature of 80 to 100 C has been reached → Diagnostic Mode 01 - Read Current System Data  ; PID 5, Coolant temperature.
• Switch ignition off.
• Start engine at a coolant temperature of 80 to 90 C and let it run at idle.

• Perform a 5 minute road test in the highest gear or in the highest driving mode on a level driving surface.

Observe safety precautions that apply to road tests → Safety Precautions .

The following operating conditions must be met during this road test:

• Engine speed approx. 1800 to 2200 RPM → Diagnostic Mode 01 - Read Current System Data  ; PID 12, engine rotations per minute (RPM)
• Vehicle speed constant 90 km/h → Diagnostic Mode 01 - Read Current System Data  ; PID 13, Vehicle speed

• Let engine run at idle.
• Under address word 33, select "Diagnostic mode 6: Check test results of components that are not continuously monitored".
• Select "Test-ID 09: Engine Coolant Temperature (ECT) sensor".
• Check specified value at idle.

Specified value: System OK

• End diagnosis and switch ignition off.

If specified value is not obtained:

• Check Engine Coolant Temperature (ECT) Sensor G62 → Engine Coolant Temperature Sensor, Checking .
• Check coolant regulator: → 19 - ENGINE - COOLING SYSTEM