View from front left in model 212.0 |
N3/9 | CDI control unit |
P07.16-3460-06
Location
The CDI control unit is located under the rights fender.
Task
The CDI control unit operates in an electrical network of sensors and actuators to form the engine management system for engine 642.8.
The following systems and functions are controlled and coordinated by the CDI control unit according to input signals:
Fuel supply
Glow system control
Injection quantity control
Diagnosis and fault storage
Engine management, start/stop function (with code B03 (ECO start/stop function))
Drive authorization system and immobilizer
Thermal management
Torque interface
Alternator interface
Exhaust gas recirculation
Exhaust treatment
The CDI control unit has an internal atmospheric pressure sensor.
Input and output signals
The following input signals are evaluated by the engine management, which also issues the corresponding output signals:
Direct input signals
Direct output signals
LIN signals
CAN input signals
CAN output signals
Direct input signals
Terminal 15
Circuit 30 (fused)
Circuit 31
Circuit 87 M1
Oil temperature sensor (B1)
Left hot film mass air flow sensor (B2/6)
Left intake air temperature sensor (B2/6b1) (model 212), left intake air temperature sensor (B2/6b1) (model 204, model 207, model 218)
Right hot film mass air flow sensor (B2/7)
Right intake air temperature sensor (B2/7b1) (model 204, model 207, model 212), right intake air temperature sensor (model 204, 207, 218)
Rail pressure sensor (B4/6)
Cylinder 1 combustion chamber pressure sensor (B4/34)
Cylinder 2 combustion chamber pressure sensor (B4/35)
Cylinder 3 combustion chamber pressure sensor (B4/36)
Cylinder 4 combustion chamber pressure sensor (B4/37)
Cylinder 5 combustion chamber pressure sensor (B4/38)
Cylinder 6 combustion chamber pressure sensor (B4/39)
Boost pressure sensor (B5/1)
Camshaft Hall sensor (B6/1)
Coolant temperature sensor (B11/4) (model 204, model 207, model 212), coolant temperature sensor (B11/4) (model 218)
Charge air temperature sensor (B17/8)
Temperature sensor upstream of SCR catalytic converter (B16/15) (with code U42 (BlueTEC (SCR)diesel exhaust treatment)) (model 207, 212 to 31. 08. 2014, 218 to 31. 08. 2014), (with code U77 (BlueTEC (SCR)diesel exhaust treatment)) (model 207, 212 as of 1. 09. 2014, 218 as of 1. 09. 2014)
Temperature sensor upstream of catalytic converter (B19/7)
Temperature sensor upstream of diesel particulate filter (B19/9) (with code 474 (Particulate filter))
Temperature sensor upstream of turbocharger (B19/11)
Temperature sensor upstream of diesel particulate filter (B19/14) (with code 474 (Particulate filter))
Pressure sensor downstream of air filter (B28/5)
DPF differential pressure sensor (B28/8) (with code 474 (Particulate filter))
Accelerator pedal sensor (B37) - potentiometer 1
Accelerator pedal sensor - potentiometer 2
Fuel temperature sensor (B50)
Exhaust pressure sensor (B60)
Crankshaft Hall sensor (B70)
Fuel filter condensation sensor with heating element (B76/1)
On-board electrical system battery (G1)
Oxygen sensor upstream of catalytic converter (G3/2)
Circuit 15 relay (N10/1kJ)
Engine circuit 87 relay (N10/1kJ)
Supplemental Restraint System control unit (N2/10)
Oil level check switch (S43)
Clutch pedal switch (S40/3)
Start enable clutch pedal switch (S40/5) with CODE B03 (ECO start/stop function))
Internal combustion engine and air conditioning fan motor with integrated control (M4/7), diagnostic data
Glow plugs (R9)
Direct output signals
Oxygen sensor heater upstream of catalytic converter (G3/2r1)
Throttle valve actuator (M16/6)
Intake port shutoff actuator motor (M55)
Fuel pump relay (N10/2kD) (model 207.3 up to 11/2009 and for model 212.0 up to 08/2009)
Circuit 15 relay (N10/1kJ)
Starter circuit 50 relay (N10/1kJ)
Engine circuit 87 relay (N10/1kJ)
Vent line heater element (R39/1)
Condensation sensor for fuel filter with heating element
Combustion engine and air conditioning fan motor with integrated control - specified fan speed
Accelerator pedal sensor - potentiometer 1 and 2
Exhaust gas recirculation actuator (Y27/9)
Pressure regulating valve (Y74)
Cylinder 1 fuel injector (Y76/1)
Cylinder 2 fuel injector (Y76/2)
Cylinder 3 fuel injector (Y76/3)
Cylinder 4 fuel injector (Y76/4)
Cylinder 5 fuel injector (Y76/5)
Cylinder 6 fuel injector (Y76/6)
Boost pressure positioner (Y77/1)
Exhaust gas recirculation cooler bypass switchover valve (Y85)
Quantity control valve (Y94)
Fuel system control unit (N118) (model 204, model 207.3 as of 12/2009, model 207.4, 212.0 as of 09/2009, model 212.2, model 218) - fuel pump ground signal ON
LIN signals
Alternator interface via drive LIN (LIN C1)
Alternator (G2)
Glow output stage (N14/3), to control various glow functions and send system errors
Fuel filter condensation sensor with heating element actuation heating element and condensation status sensor (as of 06/10)
CAN input signals
Input messages via the chassis CAN (CAN E) or chassis CAN 1 (CAN E1)
The CAN input or output signals are read in or issued for all models via the chassis CAN until modification year 2013/ model year 2014. For models 207, 212, and 218.3 as of modification year 2013 (modification year)/ model year 2014 the CAN input or output signals are read in or issued via chassis CAN 1. See respective function schematic for partial function for detailed information.
Instrument cluster (A1)
Fuel reserve signal
For model 207/212 and 218.3 as of modification year 13 routed onto the chassis CAN 1 from the front SAM control unit with fuse and relay module (N10/1).
Supplemental Restraint System control unit (N2/10) (model 204), Supplemental Restraint System control unit (N2/10) (model 207, 212, 218)
Crash signal
Automatic air conditioning control and operating unit (N22/7)
Specified fan speed request
Air conditioning, status
Routed on the chassis CAN 1 or chassis CAN from front SAM control unit with fuse and relay module.
Electronic Stability Program control unit (N30/4) (except code 233 (DISTRONIC PLUS)) or Electronic Stability Program Premium control unit (N30/7) (with code 233 (DISTRONIC PLUS))
Vehicle speed
Wheel speed signal
Brake recognition
Cruise control request
Engine torque request
Radar sensors control unit (N62/1) (model 207 up to 31.5.11 with code 233 (DISTRONIC PLUS), model 212 up to 31.5.10 with code 233 (DISTRONIC PLUS) or code 234 (Blind Spot Assist)
Engine torque request
Video and radar sensor system control unit (N62/2) (with code 233 (DISTRONIC PLUS) or with code 237 (Active Blind Spot Assist) or with code 238 (Active Lane Keeping Assist) (model 204 as of 1.6.11, model 207 as of 1.6.11, model 212 as of 1.6.10, model 218 up to model year 2015)
Engine torque request
Radar sensors control unit (N62/1) (with code 23P (Driver Assistant Package) (model 207, model 212 as facelift 13), (model 218 as of model year 2015)
For model 207/212 as of modification year 13 routed from chassis gateway control unit (N93/7)
Left front door control unit (N69/1)
Driver door closed
Routed on the chassis CAN 1 or chassis CAN from front SAM control unit with fuse and relay module.
Upper control panel control unit (N72/1)
Status button for ECO start/stop function (N72/1s50) (with code B03 (ECO start/stop function))
Routed on the chassis CAN 1 or chassis CAN from front SAM control unit with fuse and relay module.
Electronic ignition lock control unit (N73)
Start enable (drive authorization system)
Steering column tube module control unit (N80)
Steering wheel angle
Steering wheel angular velocity
Chassis gateway control unit (N93/7) (model 207, model 212 as facelift 13), (model 218 as of model year 2015) (with code 23P (Driver Assistant Package)
Engine torque request
Input messages via the drive train CAN (CAN-C)
Fuel system control unit (model 204, model 207.3 as of 12/2009, model 207.4, 212.0 as of 09/2009, model 212.2, model 218)
Fuel pressure
Self-diagnosis data
Requested diagnostic data
Fully integrated transmission control controller unit (Y3/8) (with code 427 (7-speed automatic transmission) up to 31.08.2013 or with code 421 (9-speed automatic transmission) as of 01.09.2013))
Gear range
Transmission mode
Current gear, target gear
Engine torque reduction request
Starter enable in selector lever position "P, N"
Engine idle target engine speed (for actuation of the torque converter lockup clutch)
Status of torque converter lockup clutch
Transmission control limp-home mode
Input messages via the drive train sensor CAN (CAN I) (with code U42 (BlueTEC (SCR)diesel exhaust treatment)) (model 204, 212 up to 31. 08. 2014, 218 up to 31. 08. 2014), (with code U77 (BlueTEC (SCR)diesel exhaust treatment)) (model 207, 212 as of 1. 09. 2014, 218 as of 1. 09. 2014)
Nitrogen oxides control unit downstream of diesel particulate filter (N37/7) (with code U42 (BlueTEC (SCR) diesel exhaust treatment) (model 212, 218), NOx sensor control unit downstream of diesel particulate filter (model 204, 207)
NOx concentration in the exhaust
O2 concentration in exhaust
Nitrogen oxides control unit downstream of SCR catalytic converter (N37/8) (with code U42 (BlueTEC (SCR) diesel exhaust treatment) (model 212, 218), NOx sensor control unit downstream of SCR catalytic converter (model 204, 207)
NOx concentration in the exhaust
O2 concentration in exhaust
AdBlue® control unit (N118/5) (with code U42 (BlueTEC (SCR)diesel exhaust treatment)) (model 204, 212 to 31. 08. 2014, 218 to 31. 8. 2014), (with code U77 (BlueTEC (SCR)diesel exhaust treatment)) (model 207, 212 as of 1. 09. 2014, 218 as of 1. 09. 2014)
Reduction agent quantity to be injected for NOx reduction
Reduction agent quantity to be injected for cooling the AdBlue® metering valve (Y129)
Fill level status in the AdBlue® container
Requested diagnostic data
CAN output signals
Output messages via the chassis CAN or chassis CAN 1
These CAN input or output signals are read in or issued for all models via the chassis CAN until modification year 2013/ model year 2014. For models 207, 212, and 218.3 as of modification year 2013 (modification year 13)/ model year 2014 (model year 14) the CAN input or output signals are read in or issued via the chassis CAN 1. See respective function schematic for partial function for detailed information.
Instrument cluster
Fuel consumption (the trip computer is informed about the current fuel consumption by means of square-wave pulse packages (1 pulse = 0.2 l/h))
Engine oil level too low
Circuit 61 signal (generated by CDI control unit)
Electronic ignition lock control unit
Start enable request (drive authorization system)
Output messages via the drive train CAN (CAN C)
Fuel system control unit (model 204, model 207.3 as of 12/2009, model 207.4, 212.0 as of 09/2009, model 212.2, model 218)
Fuel pump ON
Fuel specified pressure
Diagnosis request
Engine speed
Engine load
Kickdown
Engine speed limitation active
Limp-home mode engine management
Fully integrated transmission control controller unit (Y3/8) (with code 427 (7-speed automatic transmission) or code 421 )9-speed automatic transmission))
Requests for catalytic converter heating
Shift request
Engine torque
Engine coolant temperature
Engine oil temperature
Output messages via the drive train sensor CAN
AdBlue® control unit (with code U42 (BlueTEC (SCR)diesel exhaust treatment)) (model 204, 212 to 31. 08. 2014, 218 to 31. 08. 2014), (with code U77 (BlueTEC (SCR)diesel exhaust treatment)) (model 207, 212 as of 1. 09. 2014, 218 as of 1. 09. 2014)
Request for reduction agent injection
Specification of the reduction agent quantity to be injected
Specification of the run-on time of the control units
Diagnosis request
Nitrogen oxides control unit downstream of diesel particulate filter (with code U42 (BlueTEC (SCR)diesel exhaust treatment)) (model 204, to 31. 08. 2014, 218 to 31. 08. 2014), (with code U77 (BlueTEC (SCR)diesel exhaust treatment)) (model 207, 212 as of 1. 09. 2014, 218 as of 1. 09. 2014)
Diagnosis request
Nitrogen oxides control unit downstream of SCR catalytic converter, NOx sensor control unit downstream of SCR catalytic converter (with code U42 (BlueTEC (SCR)diesel exhaust treatment)) (model 204, to 212 to 31. 08. 2014, 218 to 31. 31. 2014), (with code U77 (BlueTEC (SCR)diesel exhaust treatment)) (model 207, 212 as of 1. 09. 2014, 218 as of 1. 09. 2014)
Diagnosis request
Body
The housing of the CDI control unit is made of diecast aluminum and the cover is made of corrosion-proof sheet steel. The CDI control unit is water proof and dust proof.
Power supply
The CDI control unit is "circuit 30 fused" and also energized by "circuit 87 M1" when the ignition is switched on. In the operating voltage range it has both short-circuit protection and reversed polarity protection.
Power is supplied through several engaged parallel pins connected in parallel to relieve the electrical connections.
Ground connection
The "circuit 31" ground connection is made via several ground lines to the left major assembly compartment electronics ground point (W16/5).
Information for partial function "no-load current shutoff" is documented in the function description "Engine OFF energy management function".
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.
Variants
Control unit variants CR60 all models up to modification year 13 (model year 14) and model 218.9 up to modification year 2014 (modification year 14) and model 204.
Control unit variants CR61all models as of modification year 13 (model year 14) and model 218.9 as of modification year 2014 (modification year 14) except model 204.
The variants of the engine management, for exampled country and exhaust variants, are activated with XD over the variant coding.
Wiring diagram for common rail diesel injection (CDI) control unit, N3/9 | Model 204 engine plug | ||
Model 207 engine plug | |||
Model 212 engine plug sheet 1 | |||
Model 212 engine plug sheet 2 | |||
Model 218 engine plug sheet 1 | |||
Model 218 engine plug sheet 2 | |||
Model 204 vehicle plug | |||
Model 207 vehicle plug | |||
Model 212 vehicle plug | |||
Model 218 vehicle plug |