View of engine from rear left |
N3/9 | CDI control unit |
P07.16-3594-06
Location
The CDI control unit is on the air filter housing.
Task
The CDI control unit operates in an electrical network of sensors and actuators to form the engine management system for engine 651.
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 (FBS) 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
Input signals are evaluated by the engine management and appropriate output signals are generated:
Direct input signals
Direct output signals
LIN signals
CAN input signals
CAN output signals
Direct input signals
Terminal 15
Circuit 30 (fused)
Circuit 31
Terminal 87
Knock sensor for cylinders 3+4 (A16/1) (model 207, model 212 up to 31.08.2013 except code 494 (USA version))
Knock sensor for cylinders 1+2 (A16/4) (model 207, model 212 up to 31.08.2013 except code 494 (USA version))
Oil temperature sensor (B1)
Hot film MAF sensor (B2/5)
Intake air temperature sensor (B2/5b1) (model 204, 207, 212), intake air temperature sensor (B2/5b1) ( model 218)
Rail pressure sensor (B4/6)
Combustion chamber pressure sensor for cylinder 1 (B4/34) (model 212 as of 01.09.2013 except code 494 (USA version))
Combustion chamber pressure sensor for cylinder 2 (B4/35) (model 212 as of 01.09.2013 except code 494 (USA version))
Combustion chamber pressure sensor for cylinder 3 (B4/36) (model 212 as of 01.09.2013 except code 494 (USA version))
Combustion chamber pressure sensor for cylinder 4 (B4/37) (model 212 as of 01.09.2013 except code 494 (USA version))
Boost pressure sensor (B5/1)
Boost pressure sensor for low-pressure turbocharger (B5/4) (except engine 651.913/925.)
Camshaft Hall sensor (B6/1)
Coolant temperature sensor (B11/4) ( model 204, 207, 212), coolant temperature sensor (B11/4) ( model 218)
Exhaust gas recirculation temperature sensor (B16/14) (with code (494) USA version)
Temperature sensor upstream of SCR catalytic converter (B16/15) (with code U42 (BlueTEC (SCR) diesel exhaust treatment)) (except model 207, model 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) and (with code 494 (USA version)) as of 01.09.13 (except model 207, model 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14
Charge air temperature sensor (B17/8)
Temperature sensor upstream of catalytic converter (B19/7) (with code U42 (BlueTEC (SCR) diesel exhaust treatment)) (except model 207, model 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) and (with code 494 (USA version)) as of 01.09.13 (except model 207, model 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14
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)
DPF differential pressure sensor (B28/8) (with code 474 (Particulate filter))
DPF differential pressure sensor for OBD (B2816) (with code 494 (USA version))
Transmission neutral position sensor (B79/2) (with manual transmission and with code B03 (ECO start/stop function) (except model 218)
Accelerator pedal sensor (B37) - potentiometer 1
Accelerator pedal sensor - potentiometer 2
Fuel temperature sensor (B50)
Exhaust pressure sensor (B60)
Crankshaft Hall sensor (B70) (with code B03 (ECO start/stop function))
Fuel filter condensation sensor with heating element (B76/1)
Exhaust gas recirculation cooling bypass flap Hall sensor (B90) (with code (494) USA version)
On-board electrical system battery (G1)
Oxygen sensor sensor element upstream of catalytic converter (G3/2b1)
Crankshaft position sensor (L5) (except code B03 (ECO start/stop function))
Internal combustion engine and air conditioning fan motor with integrated control (M47), diagnostic data
Engine circuit 87 relay (N10/1kJ)
Clutch pedal switch (S40/3) (with manual transmission)
Start enable clutch pedal switch (S40/5) (with a manual transmission and code B03 (ECO start/stop function))
Oil level check switch (S43)
Direct output signals
Oxygen sensor heater upstream of catalytic converter (G3/2r1)
Throttle valve actuator (M16/6)
Intake port shutoff actuator motor (M55)
Circuit 15 relay (N10/1kJ)
Starter circuit 50 relay (N10/1kJ)
Engine circuit 87 relay
Vent line heater element (R39/1)
Fuel pump relay (N10/2kD) (for model 204.0/9 up to 05/2009, model 212.0 up to 08/2009)
Coolant thermostat heating element (R48) (except code 494 (USA version))
Condensation sensor for fuel filter with heating element
Accelerator pedal sensor - reference masses for potentiometer 1 and 2
Internal combustion engine and air conditioning fan motor with integrated control - specified fan speed
Coolant pump switchover valve (Y133)
Charge air bypass flap switchover valve (Y132) (except engine 651.913/925) (up to 06/10)
Oil spray nozzle shutoff valve (Y131)
Boost pressure control pressure transducer (Y315) (except engine 651.913/925.)
Boost pressure control flap pressure transducer (Y93) (except engine 651.913/925.)
Exhaust gas recirculation actuator (Y27/9) (model 207, model 212, model 218) or exhaust gas recirculation valve (model 204)
Pressure regulating valve (Y74)
Left switchable engine mount (Y123) (for model 204.9, model 204.0/2 with 4MATIC, model 212.0/2 with 4MATIC and model 218 with 4MATIC)
Right switchable engine mount (Y123/1) (for model 204.9, model 204.0/2 with 4MATIC, model 212.0/2 with 4MATIC and model 218 with 4MATIC)
Cylinder 1 fuel injector (Y76/1)
Cylinder 2 fuel injector (Y76/2)
Cylinder 3 fuel injector (Y76/3)
Cylinder 4 fuel injector (Y76/4)
Boost pressure positioner (Y77/1) (engine 651.913/925.)
Radiator shutters actuator (Y84) (except model 204.0 with 4MATIC and model 212 with 4MATIC)
Exhaust gas recirculation cooler bypass switchover valve (Y85)
Quantity control valve (Y94)
Engine oil pump valve (Y130) (as of 06/10)
Fuel system control unit (N118) (model 204.0/9 as of 06/2009, model 204.2/3, model 207.3/4, model 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 (N143), 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
Instrument cluster (A1)
Fuel reserve signal
Supplemental restraint system control unit (N2/10) (model 204), Supplemental Restraint System control unit (N2/10) (model 207, 212, 218)
Crash signal
Electronic transmission control control unit (N15/3) (with code 423 (5-speed automatic transmission (NAG))) or fully integrated transmission control controller unit (Y3/8) (with code 427 (7-speed automatic transmission)) or (with code 421 (9-speed automatic transmission)) as of 01.09.14
Gear stage
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
AAC control and operating unit (N22/7)
Specified fan speed request
Air conditioning, status
Electronic Stability Program control unit (N304) (except code 233 (DISTRONIC PLUS)) or Electronic Stability Program Premium control unit (N30/7) (with code 233 (DISTRONIC PLUS)) (except model 204)
Vehicle speed
Wheel speed signal
Brake recognition
Cruise control request
Engine torque request
AIRmatic control unit (N51/3) (with code 489 (AIRMATIC (Air suspension with continuous adjustment damping)) (model 212, 218)
Engine start request
Engine stop prohibition
Adaptive damping system control unit (N51/5) (with code 483 (ADVANCED AGILITY package)) (model 204, 207)
Engine start request
Engine stop prohibition
Radar sensors control unit (N62/1) (with code 233 (DISTRONIC PLUS)) (model 207.3/4 up to 31.5.11, model 212.0/2 up to 31.5.10 (with code 233 (DISTRONIC PLUS )) or (with code 234 (Blind Spot Assist))
Engine torque request (increasing or reducing)
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)
Engine torque request (increasing or reducing)
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 as of 01.03.13 up to model year 2015)
Engine torque request (increasing or reducing)
Left front door control unit (N69/1)
Driver door closed
Upper control panel control unit (N72/1)
Status button for ECO start/stop function (N72/1s50) (with code B03 (ECO start/stop function)
Electronic ignition lock control unit (N73)
Start enable (drive authorization system)
Steering column tube module control unit (N80)
Steering wheel angle
Steering wheel angle speed
Chassis Gateway control unit (N93/7) (model 207, model 212 as facelift 13), (model 218 as of model year 01.09.14) (with code 23P (Driver Assistant Package)
Engine torque request
Rear axle electronic level regulation control unit (N97) (except code 489 (AIRmatic air suspension with continuous adjustment damping)) (model 212.2)
Engine start request
Engine stop prohibition
FSCU (N118) (model 204.0/9 as of 06/2009, model 204.2/3, model 207.3/4, model 212.0 as of 09/2009, model 212.2, model 218)
Fuel pressure
Self-diagnosis data
Requested diagnostic data
Nitrogen oxides control unit downstream of diesel particulate filter (with code N377) (with code U42) (BlueTEC (SCR) diesel exhaust treatment)) (except model 207, 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) and (with code 494 (USA version)) as of 01.09.13 (except model 207, 218) or NOx sensor control unit downstream of diesel particulate filter (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (model 207) or nitrogen oxides control unit downstream of diesel particulate filter (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (model 218)
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)) (except model 207, 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) and (with code 494 (USA version)) as of 01.09.13 (except model 207, 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (except model 207) or NOx sensor control unit downstream of SCR catalytic converter (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (model 207)
NOx concentration in the exhaust
O2 concentration in exhaust
AdBlue® control unit (N118/5) (with code U42 (BlueTEC (SCR) diesel exhaust treatment) (model 207, model 212, model 218) (for model up to 212.098/298) as of facelift 13) ,or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14
Reduction agent quantity to be injected for NOx reduction
The injected reduction agent quantity for cooling of the AdBlue® metering valve (Y129) (except model 207, model 218) (for model 212 (except 212.098/298) as of facelift 13) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14
Soot particulate sensor control unit (N74) (with code U42 (BlueTEC (SCR) diesel exhaust treatment) and code 494 (USA version)) (except model 207, model 218) (for model 212 (except 212.098/298) as of facelift 13)
Message concerning soot contents
CAN output signals
Instrument cluster
Engine oil level too low
Circuit 61 signal (generated by CDI control unit)
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))
Electronic ignition lock control unit
Start enable request (drive authorization system)
Fuel system control unit
Fuel pump ON
Fuel requirements
Diagnosis request
Electronic transmission control control unit (/) (with code 423 (5-speed automatic transmission (NAG))) or fully integrated transmission control controller unit (with code 427 (7-speed automatic transmission)) or (with code 421 (9-speed automatic transmission )) as of 01.09.14
Requests for catalytic converter heating
Shift request
Engine torque
Engine coolant temperature
Engine speed
Engine load
Kickdown
Engine speed limitation active
Limp-home mode engine management
Nitrogen oxides control unit downstream of diesel particulate filter (with code U42 (BlueTEC (SCR) diesel exhaust treatment)) (except model 207, 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) and (with code 494 (USA version)) as of 01.09.13 (except model 207, 218) or NOx sensor control unit downstream of diesel particulate filter (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (model 207) or nitrogen oxides control unit downstream of diesel particulate filter (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (model 218)
Diagnosis request
Nitrogen oxides control unit downstream of diesel particulate filter (with code U42 (BlueTEC (SCR) diesel exhaust treatment)) (except model 207, 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) and (with code 494 (USA version)) as of 01.09.13 (except model 207, 218) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (except model 207) or NOx sensor control unit downstream of SCR catalytic converter (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14 (model 207)
Diagnosis request
AdBlue® control unit (with code U42 (BlueTEC (SCR) diesel exhaust treatment) (model 207, model 212, model 218) (for model up to 212.098/298) as of facelift 13) ,or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14
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
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.
The inside contains the 32-bit measuring and control electronics for the engine management.
Ground connection
The "circuit 31" ground connection is made via several ground lines to the left major assembly compartment electronics ground point (W16/5).
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 engaged parallel pins connected in parallel to relieve the electrical connections.
Information about the partial function "no-load current switch off" is documented in the function description "engine OFF energy management function".
Variants
The variants of the engine management, for exampled country and exhaust variants, are activated with XD over the variant coding. Replacement of the CDI control unit is not necessary.
Assembly operations
Ensure before unplugging the connector 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 engine connector model 204 up to YoM 2011/AEJ10 | ||
N3/9 engine connector model 204 as of YoM 2011/AEJ10 | |||
N3/9 engine connector model 207 up to 31.5.11 | |||
N3/9 engine connector model 207 as of 1.6.11 | |||
N3/9 engine connector model 207 as of 1.5.13 | |||
N3/9 engine connector sheet 1 model 212 up to 31.5.10 | |||
N3/9 engine connector sheet 2 model 212 up to 31.5.10 | |||
N3/9 engine connector model 212 as of 1.6.10 | |||
N3/9 engine connector model 212 except 212.098/ 298 Delphi | |||
N3/9 engine connector model 218 | |||
N3/9 engine connector model 204 up to YoM 2011/AEJ10 | |||
N3/9 vehicle connector model 204 as of YoM 2011/AEJ10 | |||
N3/9 vehicle connector model 204.904/997 with code (U42) BlueTEC (SCR) diesel exhaust treatment as of YoM 2013 /AEJ12 | |||
N3/9 vehicle connector model 207 up to 31.5.11 | |||
N3/9 vehicle connector model 207 as of 1.6.11 | |||
N3/9 vehicle connector model 207 as of 1.5.13 | |||
N3/9 vehicle connector model 212 except 212.08 /09 /28 /29 | |||
N3/9 vehicle connector model 212.08 /09 /28 /29 | |||
N3/9 vehicle connector model 212 except 212.08 /09 /28 /29 as of 1.6.10 | |||
N3/9 engine connector model 212 except 212.098/ 298 Delphi | |||
N3/9 vehicle connector model 218 |