The automatic transmission fluid(ATF) temperature sensor is installed in the Valve Body. This sensor uses a thermistor whose resistance changes according to the temperature changes. The TCM supplies a 5V reference voltage to the sensor, and the output voltage of the sensor changes when the ATF temperature varies. The automatic transmission fluid(ATF) temperature provides very important data for the TCM’s control of the Torque Converter Clutch, and is also used for many other purposes.
This DTC code is set when the ATF temperature output voltage is lower than a value generated by thermistor resistance, in a normal operating range, for approximately 1 second or longer. The TCM regards the ATF temperature as fixed at a value of 80 °C.
Item
Detecting Condition
Possible Cause
DTC Strategy
Electrical Check
Open in circuit
Faulty sensor
Faulty PCM
Case 1
Enable Conditions
ATF temperature(IG ON) = -38?
Threshold Value
Voltage > 4.8V
Case 2
4.547V < Voltage < 4.8V
Case 3
ATF temperature(IG ON) = -39?
Engine speed > 1000rpm
Output Speed = 500rpm
Engine Coolant Temperature = 70?
Time Delay = 160 sec
Voltage > 4.547V
Diagnostic Time
More than 1sec.
Fail Safe
Learning control and Intelligent shift are inhibited
Fluid temperature is regarded as 80?
Temperature ?(?)
Resistance (?)
Resistance (k?)
-40(-40)
139.5
80(176)
1.08
-20(-4)
47.7
100(212)
0.63
0(32)
18.6
120(248)
0.38
20(68)
8.1
140(284)
0.25
40(104)
3.8
160(320)
0.16
60(140)
1.98