Park/Neutral Position Switch Malfunction (A/T Only) - Toyota T100 1996 Service Manual

DI−114
DTC P1780
CIRCUIT DESCRIPTION
The park/neutral position switch goes on when the shift lever is in the N or P shift position. When it goes on
terminal NSW of the ECM is grounded to body ground via the starter relay, thus the terminal NSW voltage
becomes 0 V. When the shift lever is in the D, 2, L, or R position, the park/neutral position switch goes off,
so the voltage of ECM. Terminal NSW becomes battery positive voltage, the voltage of the ECM internal
power source. If the shift lever is moved from the N position to the D position, this signal is used for air−fuel
ratio correction and for idle speed control (estimated control), etc.
DTC No.
2 or more switches are ON simultaneously for "N", "2" and
"L" position
(2 trip detection logic)
When driving under conditions (a) and (b) for 30 sec. or more
P1780
the park/neutral position switch is ON (N position):
(2 trip detection logic)
(a) Vehicle speed: 70 km/h (44 mph) or more
(b) Engine speed: 1,500 − 2,500 rpm
HINT:
After confirming DTC P1780 use the TOYOTA hand−held tester to confirm the PNP switch signal from "CUR-
RENT DATA".
WIRING DIAGRAM
Refer to DTC P1780 on page DI−114.
INSPECTION PROCEDURE
Refer to DTC P1780 on DI−114.
1996 TOYOTA T100 (RM449U)
DIAGNOSTICS
Park/Neutral Position Switch Malfunction
(A/T Only)
DTC Detecting Condition
− ENGINE (3RZ−FE)
S Short in park/neutral position switch circuit
S Park/neutral position switch
S ECM
Trouble Area
DI0U5−02