Engine Coolant Temperature Receiver Gauge Malfunction

METER: METER / GAUGE SYSTEM: Engine Coolant Temperature Receiver Gauge Malfunction

Engine Coolant Temperature Receiver Gauge Malfunction

WIRING DIAGRAM





INSPECTION PROCEDURE

HINT: If there is an open or short in the engine coolant temperature sensor circuit, the ECM outputs DTCs. Perform troubleshooting with the "SFI System (DTC Check / Clear)".

PROCEDURE

1. READ VALUE OF TECHSTREAM
(a) Warm up the engine.
(b) Ignition switch off.
(c) Connect Techstream to the DLC3.
(d) Turn the ignition switch to the ON position.
(e) Turn the tester ON.
(f) Enter following menus:
(1) for Engine and ECT: Powertrain / Engine and ECT / Data List.
(g) Check values by referring to the table below.

Engine and ETC:





OK:
Coolant temperature displayed on the tester is between 80°C (176°F) and 95°C (203°F) after warning up.
NG -- GO TO SFI SYSTEM
OK -- Continue to next step.
2. INSPECT COMBINATION METER ASSEMBLY
(a) Check the input signal waveform.





(1) Remove the combination meter with connectors still connected.
(2) Connect the oscilloscope to terminal C11-36 and body ground.
(3) Start the engine.





(4) Check the signal waveform according to the condition(s) in the table below.





OK:
The waveform is displayed as shown in the illustration.
NG -- CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)
OK -- REPLACE COMBINATION METER ASSEMBLY
3. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)





(a) Disconnect the C11 and E5 connectors.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- GO TO SFI SYSTEM