Component description for CDI control unit - GF07.16-P-6000OGU
ENGINES 642.820 in MODEL 164.124 as of model year 2009/YoM 08 model refinement package
ENGINES 642.820 in MODEL 164.121/125
ENGINES 642.820 in MODEL 164.824 as of model year 2009/YoM 08
ENGINES 642.820 in MODEL 164.825
ENGINES 642.870 in MODEL 251.124/125 as of model year 2009/YoM 08
ENGINES 642.872 in MODEL 251.021/023/123 as of model year 2011/YoM 10 facelift
ENGINES 642.872 in MODEL 251.027/127 as of model year 2012/YoM 11
View of engine compartment from rear right
Location
The CDI control unit is built into the engine compartment at the right in front of the windshield.
Task
The CDI control unit performs the following tasks:
- Controlling the basic engine functions
- Reading in of sensors and signals
- Evaluation of input factors
- Output of signals and actuation of components
The CDI control unit also acts as the interface (gateway) between the three connected CAN bus systems.
Controlling the basic engine functions
- Fuel supply
- Glow system
- Injection quantity control
- Electronic accelerator
- Diagnosis and fault storage
- Drive authorization system and immobilizer
- Heat management
- Exhaust gas recirculation
- Emission control
- Torque coordination
- Engine control, start/stop function
Reading in of sensors and signals
Input factors are read in by means of the following connections:
- Direct line
- Drivetrain LIN (LIN C1)
- Engine compartment CAN (CAN C)
- Drive train sensor CAN (CAN I)
Evaluation of input factors
The input factors that have been read in are evaluated by the integrated microprocessor and the affected components are then actuated.
Output of signals and actuation of components
Initial parameter are output over the following connections:
- Direct line
- Drivetrain LIN (LIN C1)
- Engine compartment CAN (CAN C)
- Drive train sensor CAN (CAN I)
The central gateway control unit (N93) is the central interface (Gateway) for exchange of function-relevant data for control units which are connected to the various Control Area Network (CAN) bus systems.
Input factors and initial parameters for the following components are read in or issued over direct lines by the CDI control unit and are needed by the engine timing:
| Input factors over a direct line | Initial parameters over a direct line | Supplemental information |
|---|---|---|
| Terminal 15 | - | - |
| Circuit 30 (fused) | - | - |
| Circuit 31 | - | - |
| Terminal 87 | - | - |
| Oil temperature sensor (B1) | - | - |
| Left hot film mass air flow sensor (B2/6) | - | - |
| Intake air temperature sensor (B2/6b1) | - | - |
| Right hot film mass air flow sensor (B2/7) | - | - |
| Intake air temperature sensor (B2/7b1) | - | - |
| Rail pressure sensor (B4/6) | - | High pressure circuit |
| Charge pressure sensor (B5/1) | - | - |
| Camshaft Hall sensor (B6/1) | - | - |
| Coolant temperature sensor (B11/4) | - | - |
| Exhaust gas recirculation temperature sensor (B16/14) | - | - |
| Temperature sensor upstream of SCR catalytic converter (B16/15) | - | With code (U42) BlueTEC (SCR) diesel exhaust treatment |
| Charge air temperature sensor (B17/8) | - | - |
| Temperature sensor upstream of catalytic converter (B19/7) | - | With code (U42) BlueTEC (SCR) diesel exhaust treatment |
| Temperature sensor upstream of diesel particulate filter (B19/9) | - | With code (474) Particulate filter |
| Temperature sensor upstream of turbocharger (B19/11) | - | - |
| Pressure sensor downstream of air filter (B28/5) | - | - |
| Pressure differential sensor (DPF) (B28/8) | - | With code (474) Particulate filter |
| DPF differential pressure sensor for OBD (B28/16) | - | With code (U42) BlueTEC (SCR) diesel exhaust treatment and code (494) USA version |
| Accelerator pedal sensor (B37) | Accelerator pedal sensor (B37) | - |
| Fuel temperature sensor (B50) | - | - |
| Exhaust back pressure sensor (B60) | - | - |
| Crankshaft Hall sensor (B70) | - | - |
| - | Fuel filter condensation sensor with heating element (B76/1) | (with code (U41) Fuel/water separator and lubrication package) for model 164.1/8 up to 30.06.10 and for model 251.1 up to 31.07.10 or with code (71o) Retrofitting a heatable fuel filter |
| End position sensor for intake port shutoff on the left (B96/1) | - | With code (U42) BlueTEC (SCR) diesel exhaust treatment and code (494) USA version |
| End position sensor for intake port shutoff on the right (B96/2) | - | With code (U42) BlueTEC (SCR) diesel exhaust treatment and code (494) USA version |
| - | Fuel pump relay (F4kO) | - |
| - | Circuit 15 relay (F58kH) | - |
| - | Starter relay (F58kI) | - |
| - | Engine circuit 87 relay (F58kD) | - |
| O2 sensor upstream of CAT (G3/2) | O2 sensor upstream of CAT (G3/2) | - |
| Combustion engine fan motor and air conditioning with integrated control (M4/7) | Combustion engine fan motor and air conditioning with integrated control (M4/7) | - |
| Throttle valve actuator (M16/6) | Throttle valve actuator (M16/6) | - |
| - | Intake port shutoff motor (M55) | - |
| Restraint systems control unit (N2/7) | - | - |
| Control unit for fuel filter condensation sensor with heating element (N33/7) | - | With code (71o) Retrofitted heated fuel filter |
| - | Vent line heater element (R39/1) | - |
| - | Two-disk thermostat heating element (R48) | Except code (U42) BlueTEC (SCR) diesel exhaust treatment and code (494) USA version |
| Oil level check switch (S43) | - | - |
| - | Left exhaust gas recirculation controller (Y27/9) | - |
| - | Pressure regulator valve (Y74) | - |
| - | Cylinder 1 fuel injector (Y76y1) | - |
| - | Cylinder 2 fuel injector (Y76y2) | - |
| - | Cylinder 3 fuel injector (Y76y3) | - |
| - | Cylinder 4 fuel injector (Y76y4) | - |
| - | Cylinder 5 fuel injector (Y76y5) | - |
| - | Cylinder 6 fuel injector (Y76y6) | - |
| - | Boost pressure positioner (Y77/1) | - |
| - | EGR [AGR] cooler bypass flap switchover valve (Y85) | - |
| - | Quantity control valve (Y94) | - |
Input factors and initial parameters for the following components and control units are transmitted or received by the CDI control unit over the LINE or CAN and are needed by the engine timing:
| Input factors via the drivetrain LIN (LIN C1) | Initial parameters via the drivetrain LIN (LIN C1) | Supplemental information |
|---|---|---|
| Alternator (G2) | - | - |
| Glow time output stage (N14/3) | Glow time output stage (N14/3) | - |
| Input factors via engine compartment CAN (CAN C) | Initial parameters via engine compartment-CAN (CAN C) | Supplemental information |
|---|---|---|
| Instrument cluster (A1) | Instrument cluster (A1) | - |
| Restraint systems control unit (N2/7) | - | - |
| Rear SAM control unit (N10/8) | - | Via the interior CAN (CAN B) and the central gateway control unit (N93) |
| AAC [KLA] control and operating unit (N22) (except code (581) Comfort automatic air conditioning) or comfort AAC control and operating unit (N22/7) (with code (581) Comfort automatic air conditioning) | - | Via the interior CAN (CAN B) and the Central gateway control unit (N93) |
| ESP control unit (N47/5) | - | - |
| EIS [EZS] control unit (N73) | EIS [EZS] control unit (N73) | - |
| Central gateway control unit (N93) | Central gateway control unit (N93) | - |
| Steering column module (N80) | - | - |
| Diagnostic connector (X11/4) | Diagnostic connector (X11/4) | Via the diagnostic CAN (CAN D) and the central gateway control unit (N93) |
| Electric controller unit (VGS) (Y3/8) | Electric controller unit (VGS) (Y3/8) | - |
| Input factors via Drivetrain sensor CAN (CAN I) | Initial parameters via Drivetrain sensor CAN (CAN I) | Supplemental information |
|---|---|---|
| NOx control unit downstream of diesel particulate filter (N37/7) | NOx control unit downstream of diesel particulate filter (N37/7) | With code (U42) BlueTEC (SCR) diesel exhaust treatment |
| NOx control unit downstream of SCR catalytic converter (N37/8) | NOx control unit downstream of SCR catalytic converter (N37/8) | With code (U42) BlueTEC (SCR) diesel exhaust treatment |
| Soot particulate sensor control unit (N74) | - | As of YoM J12 with code (U42) BlueTEC (SCR) diesel exhaust treatment and code (494) USA version |
| AdBlue® control unit (N118/5) | AdBlue® control unit (N118/5) | With code (U42) BlueTEC (SCR) diesel exhaust treatment |
Design
The housing of the CDI control unit is made of die-cast aluminum and the cover is made of corrosion-proof sheet steel. The CDI control unit is water proof and dust proof.
The housing contains the 32-bit measuring and control electronics for the engine control.
The CDI control unit has an internal atmospheric pressure sensor.
Ground connection
The ground connection "circuit 31" is made via a number of ground lines to the right major assemblies compartment ground, power ground (W16/4).
Power supply
The CDI control unit is supplied with power by "circuit 30 fused" and, with the ignition on, by "circuit 87". In the operating voltage range it has both short-circuit protection and reversed polarity protection.
Power is supplied through several pins connected in parallel to relieve the electrical connectors.
No-load current shutoff
Information for partial function "no-load current shutoff" is documented in the function description "Energy management engine OFF function".
Variants
The engine control variants, such as country and exhaust gas variants, are activated with the Diagnosis Assistance System (DAS) using the variant coding function.
Replacement of the CDI control unit is not necessary.
Assembly operations
Ensure before unplugging the plug on the CDI control unit that the ignition is switched off and processor run-on has ended. This is to prevent damage to the CDI control unit and save errors in the control units linked to the CAN.
| Wiring diagram for common rail diesel injection (CDI) control unit | N3/9 | Vehicle connector (Specification 1) model 164.1/8 | PE07.16-P-2101-97MAE | |
| N3/9 | Vehicle connector (Specification 1) model 251 | PE07.16-P-2101-97RAC | ||
| Wiring diagram for common rail diesel injection (CDI) control unit | N3/9 | Engine connector (Specification 2) model 164.1/8 | PE07.16-P-2101-97MAF | |
| N3/9 | Engine connector (Specification 2) model 251 | PE07.16-P-2101-97RAD |