Intake Air Temp. Circuit Malfunction - Toyota T100 1996 Service Manual

DTC P0110
CIRCUIT DESCRIPTION
(fig.1)
30
20
10
5
3
2
1
0.5
0.3
0.2
0.1
− 20 0 20
(− 4) 32 68
Temp.°C (F°)
DTC No.
P0110 Open or short in intake air temp. sensor circuit
HINT:
After confirming DTC P110 use the OBD II scan tool or TOYOTA nand−held tester to confirm the intake air
temp. from "CURRENT DATA".
Temp. Displayed
− 40°C (− 40°F)
140°C (284°F) or more
1996 TOYOTA T100 (RM449U)
DIAGNOSTICS

Intake Air Temp. Circuit Malfunction

Acceptable
40 60 80 100
104 140 176 212
FI4741
DTC Detecting Condition
− ENGINE (3RZ−FE)
The intake air temp. sensor is built into the air cleaner cap and
sensors the intake air temp.
A thermistor built in the sensor changes the resistance value
according to the intake air temp. The lower the intake air temp.,
the greater the thermistor resistance value, and the higher the
intake air temp., the lower the thermistor resistance value (See
fig.1).
The intake air temp. sensor is connected to the ECM (See be-
low). The 5 V power source voltage in the ECM is applied to the
intake air temp. sensor from the terminal THA via a resistor R.
That is, the resistor R and the intake air temp. sensor are con-
nected in series. When the resistance value of the intake air
temp. sensor changes in accordance with changes in the intake
air temp., the potential at terminal THA also changes. Based on
this signal, the ECM increases the fuel injection volume to im-
prove driveability during cold engine operation.
If the ECM detects the DTC "P0110", it operates the fail safe
function in which the intake air temp. is assumed to be 20°C
(68°F).
S Open or short in intake air temp. sensor circuit
S Intake air temp. sensor
S ECM
Trouble Area
Malfunction
Open circuit
Short circuit
DI−27
DI0TE−03