General Information

General Information

• Additional information:

=> Owner's Manual

426 2009 Start/Stop System



General Description:

The Start/Stop System reduces fuel consumption by turning off the engine when the vehicle is at a standstill and turning the engine back on when the driver starts to drive. The Stop/Start System works automatically when the vehicle is driven for approximately four seconds at a minimum of 3 km/h.

DTC recognition and display:

The software in the engine control module (J623) controls the Start/Stop System.

The engine control module (J623) has On Board Diagnostic (OBD) capabilities that aid in troubleshooting.

The "Guided Fault Finding" function is to be used for troubleshooting of one of the systems described as in chapter "Vehicle Diagnosis, Testing and Information System" => [ Vehicle Diagnosis, Testing and Information Systems ]

Battery recharging or battery jump start terminal on vehicles with the start/stop system

When recharging or jump starting the battery in vehicles with the Start/Stop System, note the following: First connect the positive terminal with a charging cable and then the vehicle body ground. This ensures that the battery sensor is not bridged. Charging the battery directly on the ground terminal will bridge the battery sensor and the battery data will not be recognized by the sensor during the charging process. The stored values in the data bus diagnosis interface regarding the condition of the battery will not match the values for the charged battery.

Replacing the battery on a vehicle with the Start/Stop System:

Vehicles with the Start/Stop System have a special starter battery due to the increased load on the cycles.

For the correct starter battery, refer to the => Parts Catalog. Starter batteries for vehicles with the Start/Stop System have "AGM" (Absorbent Glass Mat) or "EFB" (Enhanced Flooded Battery) marked on them.

The following parts comprise the start-stop system:

• Battery (A)

• Generator (C)

• Voltage regulator (C1)

• Starter (B)

• Brake lamp switch (F)

• Clutch pedal switch (F36)

• Start/Stop mode button (E693)

• Coolant temperature sensor (G62)

• Accelerator pedal position sensor (G79)

• Transmission neutral position sensor (G701)

• ABS control module with EDS (J104)

• Climatronic control module (J255)

• Instrument Cluster Control Module (J285)

• Battery Monitoring Control Module (J367)

• Power steering control module (J500)

• Vehicle electrical system control module (J519)

• Voltage stabilizer (J532)

• Data Bus On Board Diagnostic Interface (J533)

• Engine Control Module (J623)

• Parallel Parking Assistance Control Module (J791)