VMI3 Basic Usage Guide: Engine Coolant Temperature Sensor (ECTS) Dual Display Analysis and Simulation Guide

Step 1: Preparation and Probe Connection

• Test vehicle: KONA (SX2) G1.6 T-GDI
• Measurement target: Engine Coolant Temperature Sensor (ECTS)
• Probe connection (Channel B):
  • (+) Probe: Connect to pin 12 (sensor signal line) of the ECTS connector.
  • (-) Probe: Connect to the battery (-) terminal (vehicle body ground).
• Measurement condition: Proceed with the engine not started, in [IG ON] state.

Step 2: Dual Display – Checking Voltage Value Synchronisation

Compare the sensor voltage (data) recognised by the ECU with the actual voltage (multimeter) measured by the VMI3 hardware.

• In the Dual Display menu, activate [Data Analysis)] and [Multimeter].
• Data Analysis: Select the item 'Water Temperature Voltage'.
• Multimeter: Set to 'Voltage' measurement mode and check whether the two voltage values match. (For example: check if both show 2.65V)

Step 3: Simulation – Outputting Simulated Voltage

Test whether the ECU calculates the temperature correctly by forcibly changing the voltage using the VMI3.

• Change the lower screen to [Simulation] mode, and set the output method to 'Voltage Output'.
• Checking ECU response according to voltage change (NTC characteristics):
  • VMI3 output 1.5V ➔ Data analysis temperature shows about 45.8°C
  • VMI3 output 1.0V ➔ Data analysis temperature shows about 58.5°C (temperature rises as voltage drops)
  • VMI3 output 0.3V ➔ Data analysis temperature shows about 95.2°C