LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mercedes Benz >> 2021 >> G63 AMG >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Mixture Formation - 463 Chassis (2 Of 4) >> Basic Knowledge >> (Component Description For CDI Control Unit - GF07.16-P-6000OIB)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

(Component Description For CDI Control Unit - GF07.16-P-6000OIB)

Engine 656.9 in model 463 

View of the engine from above 

G13655874Courtesy of MERCEDES-BENZ USA

Location 

The CDI control unit is on the air filter housing.

Task 

The CDI control unit performs the following tasks:

In the electrical network with the sensors and actuators, the CDI control unit forms the engine management system for engine 656. The CDI control unit also acts as the interface (gateway) between the three connected CAN bus systems.

Controlling the engine basic functions 

Reading in of signals 

Input factors are read in over the following connections:

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:

IMPORTANT The electronic ignition lock control unit (N73) is the central interface (Gateway) for exchanging the function-relevant data of the control units that are connected to the various CAN bus systems.

Input factors and initial parameters for the following assembly parts are read in or output over direct lines by the CDI control unit and are needed by the engine management:

Input factors over a direct line Initial parameters over a direct line Supplemental information
Terminal 15 - -
Circuit 30 (fused) - -
Circuit 31 - -
Terminal 87 - -
Engine oil temperature sensor (B1) - -
Hot film mass air flow sensor (B2/5) - -
Intake air temperature sensor (B2/5b1) - -
High pressure fuel pressure sensor (B4/6) - -
Fuel pressure sensor (B4/7) - -
Boost pressure sensor (B5/1) - -
Low-pressure turbocharger boost pressure sensor (B5/4) - -
Camshaft Hall sensor (B6/1) - -
Coolant temperature sensor (B11/4) - -
Charge air temperature sensor (B17/8) - -
Temperature sensor upstream of catalytic converter (B19/7) - With code U79 (BlueTEC (SCR) diesel exhaust treatment Generation 3)
Temperature sensor upstream of diesel particulate filter (B19/9) - -
Temperature sensor upstream of ATL (B19/11) - -
DPF differential pressure sensor (B28/8) - -
Low pressure EGR differential pressure sensor (B28/18) - -
Engine oil fill level sensor (B40/6) - -
Fuel temperature sensor (B50) - -
Exhaust pressure sensor (B60) - -
Crankshaft Hall sensor (B70) - -
Low pressure exhaust gas recirculation temperature sensor (B157/2) - -
- Starter circuit 50 relay (K40/8kH) -
Circuit 87M relay (K40/8kN) Circuit 87M relay (K40/8kN) -
Circuit 15 relay (K40/8kG) - -
Throttle valve actuator (M16/6) Throttle valve actuator (M16/6) -
- Intake port shutoff actuator motor (M55) -
Supplemental Restraint System control unit (N2/10) - Direct crash signal
- Fuel pump control unit (N118) -
- Vent line heater element (R39/1) -
Engine oil pressure sensor (B42) - -
- Low pressure exhaust gas recirculation actuator (Y27/7) -
- High-pressure exhaust gas recirculation actuator (Y27/8) -
- 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) -
- Engine oil pump valve (Y130) -
- Oil spray nozzle shutoff valve (Y131) -
- Coolant pump switchover valve (Y133) -

Input and initial parameters for the following assembly parts and control units are transmitted or received by the CDI control unit via the LIN or CAN and are needed by the engine management system:

Input factors via the drive-LIN (LIN C1) Initial parameters via the drive-LIN (LIN C1) Supplemental information
Alternator (G2) Alternator (G2) -
Glow output stage (N14/3) Glow output stage (N14/3) -
Input factors via Drivetrain CAN (CAN C1) Initial parameters via Drivetrain CAN (CAN C1) Supplemental information
Fuel pump control unit (N118) Fuel pump control unit (N118) -
Fully integrated transmission control unit (Y3/8n4) Fully integrated transmission control unit (Y3/8n4) -
Powertrain control unit (N127) Powertrain control unit (N127) -
Input factors over engine CAN (CAN C) Initial parameters via engine CAN (CAN C) Supplemental information
Instrument cluster (A1) Instrument cluster (A1) Via user interface CAN (CAN HMI), electronic ignition lock control unit (N73), chassis FlexRay (Flex E) and powertrain control unit (N127)
Head unit (A26/17) - Via user interface CAN (CAN HMI), electronic ignition lock control unit (N73), chassis FlexRay (Flex E) and powertrain control unit (N127)
Audio/COMAND control panel (A40/9) - Via telematics CAN (CAN A), head unit (A26/17), user interface CAN (CAN HMI), electronic ignition lock control unit (N73), chassis FlexRay (Flex E) and powertrain control unit (N127)
Supplemental Restraint System control unit (N2/10) - Via user interface CAN (CAN HMI), electronic ignition lock control unit (N73), chassis FlexRay (Flex E) and powertrain control unit (N127)
Front SAM control unit (N10/6) - Via interior CAN (CAN B), electronic ignition lock control unit (N73), suspension FlexRay (Flex E) and powertrain control unit (N127)
Climate control, control unit (N22/1) - Via interior CAN (CAN B), electronic ignition lock control unit (N73), suspension FlexRay (Flex E) and powertrain control unit (N127)
Electronic Stability Program control unit (N30/4) - Via chassis FlexRay (Flex E) and powertrain control unit (N127)
AIRMATIC control unit (N51/3) (with CODE 489 (AIRMATIC)) - Via chassis FlexRay (Flex E) and powertrain control unit (N127)
Intelligent Drive control unit (N62/4) (with code 23P (Driving assistance package Plus)) - Via chassis FlexRay (Flex E) and powertrain control unit (N127)
Left front door control unit (N69/1) - Via interior CAN (CAN B), electronic ignition lock control unit (N73), suspension FlexRay (Flex E) and powertrain control unit (N127)
Electronic ignition lock control unit (N73) Electronic ignition lock control unit (N73) Via chassis FlexRay (Flex E) and powertrain control unit (N127)
Steering column tube module control unit (N80) - Via chassis FlexRay (Flex E) and powertrain control unit (N127)
Powertrain control unit (N127) Powertrain control unit (N127) -
Diagnostics connection (X11/4) Diagnostics connection (X11/4) Via diagnostic CAN (CAN D), electronic ignition lock control unit (N73), chassis FlexRay (Flex E) and powertrain control unit (N127)
Input factors via Drivetrain sensor CAN (CAN I) Initial parameters via Drivetrain sensor CAN (CAN I) Supplemental information
NOx sensor control unit upstream of diesel oxidation catalytic converter (N37/12) NOx sensor control unit upstream of diesel oxidation catalytic converter (N37/12) With code U79 (BlueTEC (SCR) diesel exhaust treatment Generation 3)
NOx sensor control unit downstream of SCR catalytic converter (N37/8) NOx sensor control unit downstream of SCR catalytic converter (N37/8) With code U79 (BlueTEC (SCR) diesel exhaust treatment Generation 3)
AdBlue® control unit (N118/5) AdBlue® control unit (N118/5) With code U79 (BlueTEC (SCR) diesel exhaust treatment Generation 3)

Structure 

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.

IMPORTANT The CDI control unit has an internal atmospheric pressure sensor.

Ground connection 

"Circuit 31" ground connection is connected over multiple ground lines to the firewall ground point.

Voltage supply 

The CDI control unit is supplied with power by "circuit 30 fused" and also, for 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 connections.

Variants 

The variants of the engine management, e.g. country and exhaust variants, are activated with XENTRY Diagnostics via the variant coding.

IMPORTANT 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.

Designation Unit Values Tolerance range Comment
CDI control unit (N3/9)         
On-board power supply voltage V 13, 5 -  
Voltage limits V 4...8 -  
Power consumption A 19 - Operating current
  MA 100 - Circuit 30 no-load current
Pole reverse protection - - - Yes
Additional specific parameters - - - None
Special features - - - None
Flashability/codablity - - - Yes/yes
Engine oil temperature sensor (B1)         
Version       NTC resistor (negative temperature coefficient)
Supply voltage V 5 ± 5%  
Resistor (series resistor) Ω 1470 ± 1 %  
Resistor Ω 3086, 57 - at 20°C
  - 174, 34 - At 100 °C
Hot film mass air flow sensor (B2/5)         
Supply voltage V 5 ± 0, 5  
Sensor measuring range kg/h 0...900 -  
Intake air temperature sensor (B2/5b1)         
Resistor __________________kΩ 9, 097 - At -10 °C
  - 5, 707 - at 0°C
  - 2, 437 - at 20°C
  - 1, 143 - At 40°C
  - 0, 181 - At 100 °C
High pressure fuel pressure sensor (B4/6)         
Supply voltage V 5 ± 0, 25  
Power consumption MA 15 -  
Pressure range bar 0...2200 -  
Sensor voltage V 0, 1 - For 0 bar
  - 0, 9 - For 2200 bar
Resistance (pull-up resistor) __________________kΩ 4, 64 ± 1 %  
Fuel pressure sensor (B4/7)         
Supply voltage V 5 -  
Pressure range MPa 0, 05...1 -  
Boost pressure sensor (B5/1)         
Supply voltage V 5 ± 0, 5  
Pressure measurement range kPa 10...400 -  
Power consumption MA max. 15 -  
Pull-up resistance __________________kΩ 10...55 ± 3 % For 1200 hPa
Camshaft Hall sensor (B6/1)         
Supply voltage V 4, 75...18 -  
Power consumption MA < 10 -  
Signal voltage V 0...18 -  
Signal current MA 0...20 -  
Rpm 1 rpm 0...4500 - From camshaft
Coolant temperature sensor (B11/4)         
Version - - - NTC resistor
Measuring range °C -40...140 -  
Polarity - - - Optional
Sensor voltage V 0, 83 - at 0°C
  - 1, 08 - At 100 °C
Charge air temperature sensor (B17/8)         
Version - - - NTC resistor
Supply voltage V 5 ± 5% Via CDI control unit
Resistor (series resistor) Ω 1780 ± 1 %  
Resistor Ω 5804 - at 20°C
  - 455 - at 90 °C
Sensor voltage V 3, 83 - at 20°C
  - 1, 02 - at 90 °C
Temperature sensor upstream of catalytic converter (B19/7) (with code U79 (BlueTEC (SCR) diesel exhaust treatment Generation 3))         
Version - - - PTC resistor
Sensor voltage V 0, 83 - at 0°C
  - 1, 08 - At 100 °C
Temperature sensor upstream of diesel particulate filter (B19/9)         
Version - - - PTC resistor
Resistor (series resistor) Ω 1000 -  
Supply voltage V 5 - Via CDI control unit
Resistor Ω 200, 00 - at 0°C
  - 275, 90 - At 100 °C
Sensor voltage V 0, 835 - at 0°C
  - 1, 081 - At 100 °C
Temperature sensor upstream of ATL (B19/11)         
Version - - - PTC resistor
Pressure sensor downstream of air filter (B28/11)         
Supply voltage V 5 ± 0, 25  
Resistor (pull-down resistor) __________________kΩ 220 ± 10 % To the ground connection
Pressure range kPa 7...110 -  
Signal voltage V 0, 3...4, 7 - Linear
Power consumption MA Max. 10 -  
DPF differential pressure sensor (B28/8)         
Supply voltage V 5 ± 0, 25  
Power consumption MA Max. 20 -  
Pressure range kPa -2...108 -  
Ambient temperature °C -40...140 -  
Low pressure EGR differential pressure sensor (B28/18)         
Supply voltage V 5 -  
Engine oil fill level sensor (B40/6)         
Supply voltage V 5 -  
Pressure range MPa 0, 05...1, 3 -  
Fuel temperature sensor (B50)         
Version - - - NTC resistor
Supply voltage V 5 ± 5% Via CDI control unit
Resistor (series resistor) Ω 1500 ± 1 %  
Resistor Ω 2812, 70 - at 20°C
    560, 50 - at 60°C
Exhaust pressure sensor (B60)         
Supply voltage V 5 ± 0, 25  
Ambient temperature °C -40...155 -  
Power consumption MA max. 15 -  
Signal voltage V 0, 5...4, 5 - Linear
Output current MA Max. 5 -  
Pressure measurement range kPa 50...700 -  
Crankshaft Hall sensor (B70)         
Version - - - Difference Hall sensor
Output signal V 5 - -
Low pressure exhaust gas recirculation temperature sensor (B157/2)         
Supply voltage V 5 -  
Throttle valve actuator (M16/6)         
Rated voltage V 12 -  
Power consumption A 7, 7 - Short-term 9.5 A
Sensor supply voltage V 4, 75...5, 15 -  
Resistance (pull-up resistor) __________________kΩ 10...55 -  
Frequency pulse width modulated signal Hz 2000 -  
Operating temperature °C -40...120 -  
Intake port shutoff actuator motor (M55)         
Actuator motor supply voltage V 12 -  
Nominal power consumption A 1, 3 -  
Sensor supply voltage V 5 ± 0, 2  
Maximum power consumption of the sensor MA < 15 -  
Frequency pulse width modulated signal Hz 2000 -  
No-load current actuator motor A 0, 14 -  
Reversing current actuator motor A < 8.0 -  
Glow output stage (N14/3)         
Supply voltage V 14 -  
Voltage limits V 6...16 -  
Operating current for glow output stage MA < 135 - Terminal 87
  A < 160 - Chassis 30
Preheat "ON" °C -40...1300 - Glow plug temperature
Operating current per output A Approx. 40 - Begin push phase
  - Approx. 8 - End push phase
  s approx. 2.5 - Period of the push phase
  A approx. 7 - Characteristics map glowing pulse width modulated signal
No-load current μA < 500 - Chassis 30
Cylinders 1 to 4 glow plugs (R9/1 to R9/4)         
Rated voltage V 7 -  
Power consumption (per glow plug) A 35 - At -40°C
Power consumption (per glow plug) A 5...8 - After approx. 4 s:
Resistor Ω 0, 4...0, 5 - For approx. 20°C
Basic frequency (PWM actuation) Hz 32 -  
Vent line heater element (R39/1)         
Rated voltage V 12 -  
Duty cycle % 100 - Full function
Power consumption A max. 1.9 - at 15 V
Resistor Ω 8 - at 25°C
Coolant thermostat heating element (R48)         
Rated voltage V 13, 5 -  
Supply voltage V 8 to 16 -  
Operating current A Max. 1.4 - For 60 s
Operating temperature °C -40...140 -  
Low-pressure exhaust gas recirculation actuator (Y87/5), high-pressure exhaust gas recirculation actuator (Y87/6)         
Supply voltage V 12 -  
Ambient temperature °C -10...130 -  
Pressure regulating valve (Y74)         
Supply voltage V 12 -  
Power consumption A 0, 15...1, 8 -  
PWM frequency kHz 1 -  
Coil resistance Ω 3, 42...3, 78 - at 20°C
Duty cycle % 0...100 -  
Fuel injector cylinders 1 to 4 (Y76/1 to Y76/4)         
Supply voltage V 110...154 -  
Charging current A Max. 18 - At 2000 bar
Parallel resistor __________________kΩ 180 ± 30  
Injection period μs 107, 5...2000 - Not for cold start
Injection pressure bar 230...20000 -  
Exhaust gas turbocharger guide vane actuator (Y77/1)         
Rated voltage V 12 -  
Supply voltage V 8 to 16 -  
Exhaust gas recirculation cooler bypass switchover valve (Y85)         
Rated voltage V 12 -  
Supply voltage V 8, 5...16 -  
Power consumption A 0, 43 -  
Ambient temperature °C -40...120 - For a maximum current strength
Total resistance of switchover valve Ω 28, 1 ± 5%  
Quantity control valve (Y94)         
Rated voltage V 12 -  
Coil resistance Ω 5, 0 ± 0, 6  
Actuation signal frequency, pulse width modulated signal Hz 400 -  
Duty cycle % 0...100 -  
Oil spray nozzle shutoff valve (Y131)         
Supply voltage V 5 -  
Engine oil pump valve (Y130)         
Rated voltage V 12 -  
Supply voltage V 8 to 16 -  
Power consumption A Max. 2.0 -  
Resistor Ω 10, 95 +1, 0/-0, 5  
Duty cycle, pulse width modulated signal % 0...100 -  
Coolant pump switchover valve (Y133)         
Supply voltage V 12 -