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.
Combustion Engine Control Unit, Basic Function - GF07.08-P-9890A
Engine All (4xWD)
Engine All (CAR)
Example illustration of engine 256
Overview
This document contains information on:
- General
- Function
General
The combustion engine control unit is the central control unit for the engine management functions. It also performs gateway functions for other control units.
The combustion engine control unit is located in the engine compartment, usually on the combustion engine.
Function
The combustion engine control unit intervenes in the following functions:
- Engine management
- Fuel system (fuel supply system, mixture formation, fuel preheating)
- Heat management
- Exhaust aftertreatment
- Charging
To execute these functions, the combustion engine control unit basically processes the following input factors:
- High-pressure side fuel pressure (fuel distribution)
- Low-pressure side fuel pressure
- Throttle valve position
- Fuel temperature
- Boost pressure
- Charge air temperature
- Coolant temperature
- Soot particulate filter pressure differential
- Crankshaft position
- Position of the camshaft
- Oil pressure
- Oil level, oil temperature, oil quality
- Low-pressure side exhaust gas recirculation temperature
- Position of low-pressure side exhaust gas recirculation actuator
- Position of high-pressure exhaust gas recirculation actuator
- Air mass
- Crash signal
The combustion engine control unit processes these input factors and basically transmits the following actuations:
- Throttle valve actuator
- Divert air switchover valve
- Fuel injectors
- For diesel engines: glow output stage
- Boost pressure control flap
- Low-pressure/high-pressure exhaust gas recirculation actuator
- Quantity control valve
- Alternator
| Additional basic functions | |||
| Pressure sensor downstream of air filter, basic function | GF07.04-P-2003A | ||
| Intake manifold Pressure sensor, basic function | Engine 282 | GF07.04-P-2008A | |
| Pressure sensor upstream of throttle valve, basic function | Engine 282 | GF07.04-P-2009A | |
| Hot film mass air flow sensor, basic function | Engine 608, 654, 656 Engine 656 | GF07.07-P-2000A | |
| Charge air Pressure and temperature sensor, basic function | Engine 139, 176, 177, 254, 256, 260, 264, 274, 279, 608 | GF09.41-P-2000A | |
| Charge air temperature sensor downstream of throttle valve, basic function | Engine 282 | GF09.41-P-2002A | |
| Boost Pressure control flap actuator, basic function | GF09.50-P-2001A | ||
| Camshaft Hall sensor, basic function | GF15.10-P-2001A | ||
| Integrated starter alternator, basic function | Model all (CAR) | GF15.40-P-1000A | |
| Belt-driven starter alternator, basic function | Engine all in model all | GF15.40-P-1001A | |
| Engine oil temperature sensor, basic function | Engine 133 | GF18.30-P-2000A | |
| Basic function of engine oil Pressure and temperature sensor | GF18.40-P-2004A | ||
| Component descriptions | |||
| Engine management (MR) control unit, component description | Engine all in model 223 | GF07.15-P-5003A | |
| Engine in all 206 models | GF07.15-P-5003C |
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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