OVERALL SYSTEM
AT-39
[RE4F04B]
D
E
F
G
H
I
J
K
L
M
A
B
AT
Revision: November 2006
2006 Altima
●
The line pressure is reduced below 60
°
C (140
°
F) to prevent
shifting shock due to low viscosity of automatic transaxle fluid
when temperature is low.
●
Line pressure is increased to a maximum irrespective of the
throttle opening when fluid temperature drops to
−
10
°
C (14
°
F).
This pressure rise is adopted to prevent a delay in clutch and
brake operation due to extreme drop of fluid viscosity at low
temperature.
SHIFT CONTROL
The shift is regulated entirely by electronic control to accommodate vehicle speed and varying engine opera-
tions. This is accomplished by electrical signals transmitted by the revolution sensor and the ECM (throttle
opening). This results in improved acceleration performance and fuel economy.
Control of Shift Solenoid Valves A and B
The shift solenoid valve performs simple ON-OFF operation. When
set to ON, the drain circuit closes and pilot pressure is applied to the
shift valve.
The TCM activates shift solenoid valves A and B according to sig-
nals from the ECM (throttle opening) and revolution sensor to select
the optimum gear position on the basis of the shift schedule memo-
rized in the TCM.
SAT006J
SAT007J
SAT008J