In models with an ISCV,( aka Idle control module, or ICV) Motronic accesses a different map for idle running conditions and this map is implemented whenever the engine speed is at idle. Other controlling factors are determined by operating conditions such as cold start and warm-up, idle condition, acceleration and deceleration. The AFR and the pulse duration are then corrected on reference to ATS, CTS, battery voltage and position of the TS (throttle switch).
Motronic calculates the AFR (air/fuel ratio) from the AFS signal and the engine speed (CAS). The basic AFR is also stored in a two dimensional map and the engine load and speed signals determines the basic injection pulse value. In addition, other factors that influence ignition timing are signals from the Electronic Throttle Control, Automatic Stability Control, Engine Torque Control and Electronic Transmission Control where all or any of these components are so fitted. Minor correction to timing are made with reference to the ATS and TS signals. The main correction factor is engine temperature (COOLANT TEMPERATURE SENSOR -CTS). The main engine load sensor is the AFS and engine speed is determined from the CAS (crank angle or crank position sensor- CPS) signal.Ĭorrection factors are then applied for starting, idle, deceleration and part and full-load operation. All actuators (Injectors, ISCV, CFSV etc), are supplied with nbv from the main relay and the ECU completes the circuit by pulsing the relevant actuator wire to earth.īasic ignition timing is stored in a two dimensional map and the engine load (AFM/MAF) and speed signals determines the ignition timing. Ignition and injection functions are also activated. When the engine is cranked or run, a speed signal from the CAS causes the ECU to earth pin 3 so that the fuel pump will run. The majority of sensors (other than those that generate a voltage such the CAS, CID, KS and OS), are now provided with a 5.0 volt reference supply from a relevant pin on the ECU. However, once the ignition is switched on the relay operation is similar to later models.
The 1987 M1.1 system relay is connected to earth and not to the ECU. A relay switched voltage supply is thus made to ECU pin 37, from terminal 87 of the main fuel injection relay. This causes the ECU to connect pin 36 to earth, so actuating the main fuel injection relay. Once the ignition is switched on, a voltage supply to ECU pin 27 (not 1987 M1.1) and to the ignition coil is made from the ignition switch. This allows the self-diagnostic function to retain data of an intermittent nature. A 55 pin connector and multi-plug connects the ECU to the battery, sensors and actuators.Ī permanent voltage supply is made from the vehicle battery to pin 18 of the ECU. The injection function of the Motronic system is based on the well tried 'L' jetronic system, although a number of refinements have improved operation. The ignition point and injection duration are jointly processed by the ECU so that the best moment for ignition and fuelling are determined for every operating condition. Although only 6 cylinder engines were equipped with M1.1, when M1.3 was introduced, both 4 and 6 cylinder engines were equipped with this later version. The Motronic EMS is a fully integrated system that controls primary ignition, fuelling and idle control from within the same ECU. 1987 versions of M1.1 contained some small differences to the 1988 version. The main differences between 1.1 and 1.3 concern the SD feature. Motronic 1.1 was first fitted to some 6 cylinder models in 1987 and was superseded in 1988 by Motronic 1.3. Motronic 1.1 and 1.3 are an evolution of the early Motronic EMS fitted to previous BMW vehicles during the early to middle 1980's. I think much of it translates to latter cars too. The 1.3 is applicable to the M20 and M30 cars. It specifically addresses early Motronic 1.0 and 1.3. I posted this over at mye28 some time back. Ok, so I see lots of confusion over what sensor does what recently.
0 kommentar(er)
