SLK 320 (170.465) V6-3.2L (112.947) (2002)
engine can be started (start enable) only once the vehicle is again unlocked with the authorized key and the drive authorization system control unit
transmits a message to this effect over the CAN databus to the ME-SFI control unit.
Engine speed signal
The ME-SFI control unit generates the short-circuit proof engine speed signal TNA from the signals supplied by the crankshaft position sensor, and
outputs it to other control units as follows:
Square-wave signal with constant on/off ratio, maximum current approx. 20 mA.
Engine 111: 2 pulses/engine revolution
Engine 104, 112, 137: 3 pulses/engine revolution
Engine 119, 113: 4 pulses/engine revolution
Engine 113 with ME 2.8: 3 pulses/engine revolution
Engine 120: 3 pulses/engine revolution (from right ME-SFI control unit)
Actuations with HHT or STAR DIAGNOSIS
Functions can be actuated specifically for diagnostic purposes. These are listed in a menu point.
Version coding
For adapting the ME-SFI control unit to different vehicle versions and vehicle equipment by means of matching code numbers. Coding is performed
with the Hand-Held Tester (HHT) or with STAR DIAGNOSIS. The following vehicle versions and equipment versions can be coded using the version
coding:
-
Vehicle model
-
National version
-
with or without TWC.
Fuel consumption signal
The fuel consumption signal (e.g. 8 l/hour) is calculated from the injection times and the current fuel consumption is advised to the trip computer by
means of square-wave pulse packages.
One square-wave pulse means 0.2 l/hour.
Note: With CAN compatible instrument cluster: Information is transmitted via CAN from the ME control unit to the instrument cluster.
Delayed-off running
After the ignition is switched off, the ME-SFI control unit performs a delayed-off run during which certain data memories are updated (e.g. the DTC
memory). The duration is dependent on the coolant temperature (at 80°C approx. 4 s, at 20°C approx. 60 s and at -30°C approx. 150 s) and whether
the engine was started after ignition ON. If the ignition is switched off without starting the engine, the run-on time is always approx. 4 s.
(USA) Engine 112.946 with code 929 Flexible Fuel Vehicle (FFV)
The engine control unit has for FFV additional functions, as identifying Ethanol portion after each fueling and adapting the mixture correspondingly