Toyota Celica 2005 Repair Manual page 1013

DI−812
DTC P0751
DTC P0756
SYSTEM DESCRIPTION
The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd or O/D
gear).
Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical
trouble of the shift solenoid valves and valve body.
DTC No.
During normal driving, the gear required by the ECM does not
P0751
match the actual gear
P0756
(2−trip detection logic)
HINT:
Check the shift solenoid valve No. 1 when DTC P0751 is output and check the shift solenoid valve No. 2
when DTC P0756 is output.
MONITOR DESCRIPTION
The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". According to the input shaft
revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual
gear position (1st, 2nd, 3rd or O/D gear position). When the gear position commanded by the ECM and the
actual gear position are not the same, the ECM illuminates the MIL and stores the DTC.
MONITOR STRATEGY
P0751
Related DTCs
Required sensors/Components
Required sensors/Components
Frequency of operation
Duration
MIL operation
Sequence of operation
2005 CELICA (RM1131U)
DIAGNOSTICS
Shift Solenoid "A" Performance
(Shift Solenoid Valve S1)
Shift Solenoid "B" Performance
(Shift Solenoid Valve S2)
DTC Detecting Condition
P0751
Main
Sub
Continuous
OFF malfunction (A)
OFF malfunction (B),
ON malfunction (A) & (B)
2 driving cycles
None
− AUTOMATIC TRANSAXLE (U341E)
S Shift solenoid valve No. 1/No. 2 is stuck open or closed
S Valve body is blocked up or stuck
S ECM
Shift solenoid valve S1/OFF malfunction
Shift solenoid valve S1/ON malfunction
Shift solenoid valve S1, Speed sensor (NT), Speed sensor (NC), Crank-
shaft position sensor (NE)
Throttle position sensor, Vehicle speed sensor
0.85 sec.
0.8 sec.
1012
Trouble Area
DIAJE−03