- Unit: °C (°F)
- If the value is -40 (-40): The sensor circuit is open
- If the value is 140 (284): The sensor circuit is shorted.
| Last Modified: 11-27-2007 | 1.6 J | |
| Service Category: Vehicle Interior | Section: Meter/Gauge/Display | |
| Model Year: 2008 | Model: LX570 | Doc ID: RM000000V7W00LX |
| Title: METER / GAUGE / DISPLAY: METER / GAUGE SYSTEM: DESCRIPTION (2008 LX570) | ||
|
Engine Coolant Temperature Gauge Malfunction |
DESCRIPTION
In this circuit, the combination meter assembly receives engine coolant temperature signals from the ECM using CAN communication lines. The combination meter assembly displays an engine coolant temperature that is calculated based on the data received from the ECM.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If there is an open or short in the engine coolant temperature sensor circuit, an SFI system DTC is output. If output, perform troubleshooting on the SFI system first.
PROCEDURE
|
1. |
CHECK CAN COMMUNICATION SYSTEM |
(a) Check for DTCs
.
Result
|
Result |
Proceed to |
|---|---|
|
CAN communication system DTC is not output |
A |
|
CAN communication system DTC is output |
B |
|
|
2. |
PERFORM ACTIVE TEST USING TECHSTREAM (COOLANT TEMP) |
(a) Operate the Techstream according to the display and select the Active Test.
Combination Meter
|
Tester Display |
Test Part |
Control Range |
Diagnostic Note |
|---|---|---|---|
|
Water Temperature Meter Operation |
Engine coolant temperature receiver gauge |
LOW, NORMAL or HIGH |
Perform the test with the vehicle stopped and the engine idling. |
HINT:
Confirm that the vehicle is stopped and the engine is idling.
OK:
Needle indication is normal.
|
|
3. |
READ VALUE USING TECHSTREAM (COOLANT TEMPERATURE) |
(a) Operate the Techstream according to the display and select the Data List.
Combination Meter
|
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|
|
Coolant Temperature |
Engine coolant temperature/Min.: -40 (-40), Max.: 140 (284) |
After warming up: 80 to 105 (176 to 221) |
|
OK:
Coolant temperature displayed on the Techstream is between 80°C (176°F) and 105°C (221°F) after warming up.
|
|
4. |
READ VALUE USING TECHSTREAM (ENGINE COOLANT TEMPERATURE) |
(a) Operate the Techstream according to the display and select the Data List.
Engine
|
Tester Display |
Measurement Item/Range |
Normal Condition |
Diagnostic Note |
|---|---|---|---|
|
Coolant Temp |
Engine coolant temperature/Min.: -40°C (-40°F), Max.:140°C (284°F) |
After warming up: 80 to 100°C (176 to 212°F) |
If the value is -40°C (-40°F): The sensor circuit is open. If the value is 140°C (284°F): The sensor circuit is shorted. |
OK:
Engine coolant temperature value displayed on the Techstream is almost the same as actual engine coolant temperature.
|
|
5. |
REPLACE COMBINATION METER ASSEMBLY |
(a) Temporarily replace the combination meter with a new one
.
|
|
6. |
CHECK COMBINATION METER ASSEMBLY |
(a) Check that the operation of the combination meter returns to normal
.
OK:
Operation of combination meter returns to normal.
|
|
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