Volvo 819 E - Ez·l02 K

Group 28 Ignition systems
Design and function - System descriptions
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EZ - 102K
EZ-102K
823FT
(760,1984 with 823FT)
The sensors supply the control unit (1) with a series of signals which descr ibe the engine running conditions . The
control unit uses the signals to compute the optimum timing and transmits the necessary ignition pulses to the
power stage (2), which makes and breaks the current in the primary winding of the i gnition coil (3). The high -
tension current thereby induced in the secondary winding is del ivered to the appropriate spark plug (4) by the
distributor (5).
The timing is computed by the control unit on the basis of the following i nformation :
-
The Hall generator in the distributor (5) supplies a signal indicating the engine speed and crankshaft position.
- The engine load signal is supplied by the LH - 2.1 injection system control unit (9) which, in turn , is supplied with a
load signal by the air mass meter (10),
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Any tendency of the engine to run hot is indicated by a thermostat (8). ( The throttle must be closed and the engine
temperature must be above 103°C before the control unit advances the timing . Under these conditions, the ther -
mostat will close, and the control unit will both advance the setting by 13° and switch in the electric radiator fan.)
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Engine knock is indicated by the knock sensor (7 ),
- Throttle closure is indicated by the throttle switch (6) .
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