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Home >> Mazda >> 2003 >> MX-5 Miata L4-1.8L DOHC >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Engine Temperature Sensor >> Testing and Inspection
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Engine Temperature Sensor: Testing and Inspection

Engine Coolant Temperature Compensation Inspection
1. Connect the WDS or equivalent to DLC-2.
2. Select following PIDs.
- ECT
- RPM

3. Verify that the engine is in cold condition, then start the engine.
4. Verify that the engine speed decreases as the engine warms up.
- If the engine speed does not decrease or decreases slowly, carry out the following:
- ECT sensor inspection
- IAC valve inspection

Load Compensation Inspection

1. Warm up the engine to normal operating temperature and idle it.
2. Connect the WDS or equivalent to DLC-2.
3. Select the following PID.
- RPM




4. Turn the electrical loads on and verify that the engine speed is within the specification.
- If not as specified, carry out following:
- Headlight switch inspection
- A/C switch inspection
- P/S pressure switch inspection
- IAC valve inspection
- Fan switch inspection
- Cooling fan motor inspection
- Rear window defroster inspection

Note: Excludes temporary idle speed drop just after the electrical loads are turned on

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