Control Module Inputs, Outputs, Power Supply

Control Module Inputs







- Mass air flow sensor
- Engine coolant temperature sensor
- Oxygen sensor
- Crankshaft position sensor
- Position sensor, camshaft
- TCM control module
- Knock Sensor
- Throttle position sensor
- Power supply +15







- Power supply +30
- Ground
- Main relay
- Connector, coding
- Main Instrument Unit, MIU

Control Module Outputs







- Injectors
- Engine speed
- Ignition pulses
- A/C relay
- Main relay
- Fuel pump relay
- CHECK ENGINE lamp (MIL)
- Diagnostics communication







- Throttle angle
- EVAP canister purge valve, carbon filter
- Idle air control valve (IAC)
- Fuel consumption
- Ground

Control Module







Control module for Motronic 2.10.3, which has 55 connections, includes functions for both ignition and fuel injection.
With help of input signals from a large number of sensors the control module instantly receives information as regards to engine load, temperature, engine speed, exhaust gas composition, possible knocking, etc.
The control module "co-ordinates" this information with the so called "Kennfeld" or "Maps" that are present in the permanent memory and controls both the ignition and fuel injection based on this information.
The control module is positioned behind the panel by the right-hand A-pillar. The cables are run via grommets in the bulkhead partition out to the engine bay. When removing the power train the control module connector is run out with the cables through the bulkhead.

Programming Manual/Automatic







The Motronic control module has the same part number for cars with manual or automatic gearboxes.
By energizing pin 40 the control module is programmed for cars with a automatic gearbox. On cars with a manual gearbox the circuit across pin 40 is open.

Coding of control module
Because component 322 (Variant Coding) has different resistors, the control module is programmed via pin 54 to be able to use different "Kennfeld" or "Maps".

Control Module Power Supply












When the ignition is turned to drive position and the control module receives the battery voltage on pin 27, the main relay pin 85 is grounded from control module pin 36 and the relay is activated. The control module receives its main power supply on pin 37 from the main relay pin 87.


NOTE: The relay stays activated for a further 5 seconds after the ignition has been switched off.


Battery Voltage+30
The Motronic control module is fed battery voltage +30 on pin 18. The control module uses the voltage to supply the maintenance current in the memory. Current consumption in the state of rest is less then 2.5 mA.


NOTE: Without +30-voltage to the control module the car will not start.


+15-voltage
With the ignition key in the drive position the control module receives +15-voltage on pin 27.
The +15-voltage is used among other things to activate the control module to ground the main relay, so that the power supply is established on pin 37.