DESCRIPTION The Automatic
Transmission Fluid (ATF) temperature sensor is on the transmission, just
in front of the oil cooler inlet pipeline. If
the ECM detects an abnormally high ATF temperature near this sensor, the
ATF temperature warning light illuminates or a message is displayed in
the combination meter.
HINT:
- The temperature of the ATF easily rises when towing, climbing hills, in traffic, etc.
- If the ATF temperature sensor becomes short-circuited, the signal that
indicates that the ATF temperature is 150°C (302°F) or higher is input
into the ECM.
Vehicle conditions when the sensor is normal and when the sensor is short-circuited are indicated in the table below.
No. 2 ATF Temperature Sensor State |
Detection Condition | Symptom |
Recovery Condition |
Sensor is normal | ATF temperature more than 150°C (302°F) |
ATF temperature warning light is illuminated or message is displayed in combination meter |
ATF temperature less than 135°C (275°F)*1 |
ATF temperature more than 130°C (266°F) |
Shift point too high | ATF temperature less than 110°C (230°F) |
When conditions (a) and (b) are satisfied. (a) ATF temperature more than 130°C (266°F)
(b) Engine coolant temperature more than 95°C (203°F) |
Lock-up in 3rd gear*2 | ATF temperature less than 110°C (230°F)*1 and engine coolant temperature more than 95°C (203°F) |
Sensor is short-circuited | Any conditions |
- ATF temperature warning light blinks or message is displayed in combination meter
- Shift point too high
| Symptoms persist |
Engine coolant temperature more than 95°C (203°F) |
Lock-up in 3rd gear*2 | Symptoms persist |
HINT: *1:
When the ATF is normal, it decreases to less than 135°C (275°F) within 5
minutes with the shift lever in P or N in an idling state. *2:
When ATF temperature is normal, transmission lock-up occurs in 5th or
6th gear with the shift lever in D or with the S6 range selected, in 5th
gear with the S5 range selected, and in 4th gear with the S4 range
selected.
DTC Code | DTC Detection Condition |
Trouble Area | P2742 |
No. 2 ATF temperature sensor resistance is less than 25 Ω (0.046 V) for 0.5 seconds or more (1-trip detection logic). |
- Short in No. 2 ATF temperature sensor circuit
- Transmission wire (No. 2 ATF temperature sensor)
- ECM
| P2743 |
No.
2 ATF temperature sensor resistance is higher than 156 kΩ (4.915 V) for
0.5 sec. or more and either condition is met (1-trip detection logic): (A)
15 min. or more have elapsed after the engine start when the engine
coolant temperature or intake air temperature is -29.375°C (-20.875°F)
or less. (B) 10 sec. or more have elapsed after the
engine start when the engine coolant temperature and intake air
temperature are higher than -29.375°C (-20.875°F). |
- Open in No. 2 ATF temperature sensor circuit
- Transmission wire (No. 2 ATF temperature sensor)
- ECM
| MONITOR DESCRIPTION
The
ATF temperature sensor converts the ATF temperature into an electrical
resistance value. Based on the resistance, the ECM determines the ATF
temperature, and the ECM detects an open or short in the ATF temperature
circuit. If the resistance value of the ATF temperature sensor is below
25 Ω*1 or higher than 156 kΩ*2, the ECM interprets this as a fault in
the ATF temperature sensor or wiring. The ECM stores a DTC, and the ATF
temperature warning light blinks or a message is displayed in the
combination meter.
HINT:
- *1: 150°C (302°F) or higher is indicated regardless of the actual ATF temperature.
- *2: -40°C (-40°F) is indicated regardless of the actual ATF temperature.
- The ATF temperature can be checked on the Techstream display.
WIRING DIAGRAM Refer to DTC P0712 (See page
). CAUTION / NOTICE / HINT
1. DATA LIST HINT: Using
the Techstream to read the Data List allows the values or states of
switches, sensors, actuators and other items to be read without removing
any parts. This non-intrusive inspection can be very useful because
intermittent conditions or signals may be discovered before parts or
wiring is disturbed. Reading the Data List information early in
troubleshooting is one way to save diagnostic time. NOTICE: In
the table below, the values listed under "Normal Condition" are
reference values. Do not depend solely on these reference values when
deciding whether a part is faulty or not. (a) Warm up the engine. (b) Turn the ignition switch off.
(c) Connect the Techstream to the DLC3. (d) Turn the ignition switch to ON.
(e) Turn the Techstream on. (f) Enter the following menus: Powertrain / Engine and ECT / Data List.
(g) According to the display on the Techstream, read the Data List. Engine and ECT
Tester Display | Measurement Item/Range |
Normal Condition | Diagnostic Note |
A/T Oil Temperature 2 | No. 2 ATF temperature sensor value/
Min.: -40°C (-40°F) Max.: 150°C (302°F) |
- After stall test: Approximately 80°C (176°F)
- Equal to ambient temperature when engine cold
| If the value is -40°C (-40°F) or 150°C (302°F), the No. 2 ATF temperature sensor circuit is open or shorted. |
HINT:
Temperature Displayed | Malfunction |
-40°C (-40°F) | Open circuit |
150°C (302°F) or more |
Short circuit | PROCEDURE
1. |
INSPECT TRANSMISSION WIRE (NO. 2 ATF TEMPERATURE SENSOR) |
(a) Disconnect the D83 transmission wire connector. | |
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition |
Specified Condition | 3 (OT2-) - 14 (OT2+) |
Always | 25 Ω to 156 kΩ |
3 (OT2-) - Body ground |
Always | 10 kΩ or higher |
14 (OT2+) - Body ground |
Always | 10 kΩ or higher |
HINT: If
the resistance is out of the specified range at any of the ATF
temperatures shown in the table below, the driveability of the vehicle
may decrease. Standard Resistance:
ATF temperature | Specified Condition |
10°C (50°F) | 5 to 8 kΩ |
25°C (77°F) | 2.5 to 4.5 kΩ |
110°C (230°F) | 0.22 to 0.28 kΩ | Text in Illustration
*a | Component without harness connected
(Transmission Wire) |
NG |
| REPAIR OR REPLACE TRANSMISSION WIRE (NO. 2 ATF TEMPERATURE SENSOR) |
OK |
| |
2. |
CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM) |
(a) Disconnect the D74 ECM connector. | |
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition |
Specified Condition | D74-99 (THO2) - D74-98 (E2) |
Always | 25 Ω to 156 kΩ |
D74-99 (THO2) - Body ground |
Always | 10 kΩ or higher |
D74-98 (E2) - Body ground |
Always | 10 kΩ or higher | Text in Illustration
*a | Front view of wire harness connector
(to ECM) |
OK |
| REPLACE ECM |
NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR | |