Toyota ZZT230 series Repair Manual page 410

DTC
Une Press u re Con·
Pressure
trol
ON
DTCNo.
(a) or
(b
P1760
GNO
)
P1760
Linear Solenoid for Line Pressure Control
Circuit Malfunction (Solenoid Valve SLT)
002290
Current
Flow to Solenoid
B
1 Cycle
(b)
DTC
Detecting
condition below Is detected 1 second or more.
sLT-
terminal: OV
12V
SLT-termlnal:
5V/ Div.
oo1a1s
msec
1 . / Div.
-
DIAGNOSTICS AUTOMATIC TRANSAXLE (U240E)
CIRCUIT DESCRIPTION
The throttle pressure that is applied to the primary regulator
valve (which modulates tine pressure) causes the solenoid
valve SLT, under electronic control, to precisely and minutely
modulate and generate line pressure according to the accelera·
tor pedal effort, or engine power output detected.
This reduces the function of line pressure and provides smooth
shifting characteristics.
Upon receiving the throttle valve opening angle signal, ECM
controls the line pressure b y sending a predetermined ("' ) duty
ratio to the solenoid valve, modulating the line pressure, gener·
atlng throttle pressure.
(•) Duty Ratio is
The duty ratio the ratio of the period of continuity in one cycle.
For example, if "A" is the period of continuity in one cycle, and
MB" is the period of non-continuity, then
Duty
Condtion
•Open or short in shift
• Shift
•ECM
Reference:
ling .
X
, � A ' + "-., 8 -
t
R
i
100 ( %)
a o
Trouble Area
SLT circuit
solenoid valve
SLT
solenoid valve
Pl-1 99