General Description For Start/Stop System

General Information 

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 Start/Stop System is integrated in the software for the Engine Control Module -J623- as a function.

The Engine Control Module -J623- is equipped with OBD.

For troubleshooting, use the Vehicle Diagnostic Tester in the "Guided Fault Finding  " function.

Battery recharging or battery jump start terminal on vehicles with the Start/Stop System

Connect the positive post first and then the body ground using a charge cable. This ensures that the Battery Monitoring Control Module -J367- is not bridged. Charging the battery directly on the negative terminal bridges the Battery Monitoring Control Module -J367- and prevents the Battery Monitoring Control Module -J367- from recording the battery data during the charging process. The values stored in the Data Bus On Board Diagnostic Interface -J533- regarding the battery charge no longer match the values for the charged battery.

Replacing the battery on vehicles with the Start/Stop System

Vehicles with a Start/Stop System only have an AGM battery as the starter battery instead of the typical lead battery due to its higher cycle life.

Refer to the Parts information for the correct part names. The components of the Stop/Start System do not have a special markings and look the same as the other components from the outside.

The following components make up the Start/Stop System:

• Battery. Refer to BATTERY .
• Generator. Refer to GENERATOR .
• Voltage Regulator -C1-. Refer to VOLTAGE REGULATOR, REMOVING AND INSTALLING .
• Starter. Refer to STARTER .
• Brake Lamp Switch -F-. Refer to FRONT BRAKE CALIPER or REAR BRAKE CALIPER .
• Clutch Pedal Switch -F36-. Refer to CLUTCH MECHANISM (0AF) , CLUTCH MECHANISM (0CG) and CLUTCH MECHANISM (02Q, 02QA) and CLUTCH (02E) .
• Start/Stop Mode Button -E693-. Refer to GENERAL DESCRIPTION FOR START/STOP SYSTEM .
• Engine Coolant Temperature Sensor -G62-. Refer to the appropriate information COOLANT SYSTEM/COOLANT (CZCA, CZDA, CZTA) , COOLANT SYSTEM/COOLANT (CBPA, CKJA) , COOLANT SYSTEM/COOLANT (CNLA, CRJA) , COOLING SYSTEM/COOLANT (CVCA, CUUA, CUUB, DELA, DEBA, DEJA, DGMA) and COOLANT SYSTEM/COOLANT (CPLA, CPPA, CPKA, CPRA) .
• Accelerator Pedal Position Sensor -G79-. Refer to ACCELERATOR MECHANISM , ACCELERATOR MECHANISM (CNLA, CPLA, CPPA, CPKA, CPRA, CBPA, CBTA, CBUA, CZTA, CBFA, CCTA) or ACCELERATOR PEDAL MECHANISM (CVCA, DEBA, DELA) .
• Transmission Neutral Position Sensor -G701-. Refer to MECHATRONIC (CBPA, CPLA, CPPA, CVCA, DEBA, DELA) and MECHATRONIC (0CG) .
• ABS Control Module -J104-. Refer to CONTROL MODULE AND HYDRAULIC UNIT .
• Climatronic Control Module -J255-. Refer to FRONT HEATER AND A/C UNIT .
• Instrument Cluster Control Module -J285-.
• Battery Monitoring Control Module -J367-.
• Power Steering Control Module -J500-. Refer to STEERING GEAR .
• Vehicle Electrical System Control Module -J519-. Refer to Vehicle Electrical System Control Module -J519-, REMOVING AND INSTALLING .
• Voltage Stabilizer -J532-. Refer to VOLTAGE STABILIZER, REMOVING AND INSTALLING .
• Data Bus On Board Diagnostic Interface -J533-. Refer to Data Bus On Board Diagnostic Interface -J533-, REMOVING AND INSTALLING .
• Engine Control Module -J623-. Refer to ENGINE CONTROL MODULE (CNLA, CRJA) , ENGINE CONTROL MODULE (CZCA, CZDA, CZTA) , ENGINE CONTROL MODULE (CBPA, CKJA) , ENGINE CONTROL MODULE (CPLA, CPPA, CPKA, CPRA) . or ENGINE CONTROL MODULE (CVCA, CUUA, CUUB, DELA, DEBA, DEJA, DGMA) .

Voltage Stabilizer -J532- 

The Voltage Stabilizer -J532- is installed inside the instrument panel behind the glove compartment. It stabilizes the voltage fluctuations in the vehicle electrical system to 12 volts, which are caused by the stop/start system.

This is what happens if the Voltage Stabilizer -J532- is faulty

If the Voltage Stabilizer -J532- is faulty and the voltage supply is insufficient, devices like the Radio/RNS or telephone will be reset. If the above-mentioned electrical equipment is reset each time the engine starts in Start/Stop mode, then this indicates a defective Voltage Stabilizer -J532-. Currently, no malfunction entry is directly logged for the Voltage Stabilizer -J532- in the DTC memory for either the Data Bus On Board Diagnostic Interface -J533- or the Vehicle Electrical System Control Module -J519-. If the radio, the radio/RNS and the telephone all malfunction at the same time, first check the fuse for the Voltage Stabilizer -J532-. Refer to the Appropriate Wiring Diagram.

Start/Stop Mode Button -E693- 

The Start/Stop Mode Button -E693- is located with the switches inside the center console in front of the gearshift lever. The switch manually switches the Start/Stop System on and off.

Start/Stop Mode Button -E693-, Removing and installing. Refer to Start/Stop Mode Button -E693-, REMOVING AND INSTALLING .