Suzuki 2007 XL7, Руководство по обслуживанию

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5A-6 Automatic Transmission:
Automatic Transmission Input Speed (A/T ISS)
Sensor Assembly (73)
The A/T ISS sensor operates identically to the A/T OSS
sensor except it uses the stamped teeth on the forward
and direct clutch housing assembly - with input shaft
(567) as the rotor (reluctor). Remember that the forward
and direct clutch housing assembly - with input shaft is
driven at converter turbine speed. The A/T ISS sensor
square wave form is also compared to a fixed clock
signal internally within the TCM to determine actual
converter turbine speed. The TCM uses transmission
input and output speeds to help determine line pressure,
transmission shift patterns, TCC apply pressure, gear
ratios, and TCC slippage for diagnostic purposes.
Shift Solenoid Valves
The AF33-5 uses five electromagnetic shift solenoid
valves to control upshifts and downshifts in all forward
gear ranges. These shift solenoid valves are controlled
by the TCM and work together in a combination of ON
and OFF sequences to control the various shift valves.
The TCM uses numerous inputs to determine which
solenoid state combination the transmission should be
in. The following table shows the solenoid state
combination required for each gear range. Refer to “Shift
Solenoid Valve State and Gear Ratio”.
Normally Open Shift Solenoid Valves
Three of the shift solenoid valves used in the AF33-5
(the reverse, 1st SS valve; the 2-3, 3-4 SS valve; and the
3-4, 4-5 SS valve) are referred to as normally open
solenoid valves. Normally open shift solenoid valves are
de-energized (turned OFF) when the TCM opens the
path to ground for the solenoid's electrical circuit. With
the solenoid OFF, signal fluid moves the metering ball
and plunger away from the exhaust seat. This allows
signal fluid to flow past the metering ball and exhaust
through the solenoid. As a result of this exhaust, there is
no pressure in the signal fluid circuit when the normally
open solenoid is OFF. When the TCM provides a path to
ground for the electrical circuit to energize (turn ON) the
solenoid, current flows through the coil assembly in the
solenoid and creates a magnetic field. The magnetic
field moves the plunger inside the solenoid and seats the
metering ball against the exhaust seat, thereby blocking
the exhaust passage and causing signal fluid pressure to
increase.
Normally Closed Shift Solenoid Valves
The remaining two shift solenoid valves used in the
AF33-5 (the 1-2, 2-3, reverse SS valve and the reverse
SS valve) are referred to as normally closed solenoid
valves. Normally closed shift solenoid valves function
similar to normally open shift solenoid valves in that the
TCM controls the path to ground for the electrical circuit
to turn the solenoid ON or OFF. The normally closed shift
solenoid valves are de-energized (turned OFF) when the
TCM opens the path to ground for the solenoid's
electrical circuit. However, when a normally closed
solenoid is OFF, spring pressure seats the plunger and
metering ball against the exhaust seat, thereby blocking
the exhaust passage and causing signal fluid pressure to
increase. When the TCM provides a path to ground for
the electrical circuit to energize (turn ON) the solenoid,
current flows through the coil assembly in the solenoid
and creates a magnetic field. The magnetic field moves
the plunger against spring force and moves the metering
ball away from the exhaust seat. This allows signal fluid
to flow past the metering ball and exhaust through the
solenoid. As a result of this exhaust, there is no pressure
in the signal fluid circuit when the normally closed
solenoid is ON.