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CosmicBike · Feb 4th, 2020, 18:08

Numbers, interspersed with painting, dog walking and cooking.

COLD (as in not started, ambient circa 10 degrees C)

Sensor only, measured directly on sensor terminals: 9.04k Ohms

All other measurements taken at pins 5 & 13 on ECU.

Sensor connected: 4.57k Ohms

Sensor disconnected: Open Loop (infinity Ohms)

Sensor plug shorted: 860 Ohms

And after re-connecting the ECU and battery, followed by a 14 mile drive to the dump and to fill with petrol. Temperature gauge just below mid-point when I returned to the driveway.

Hot to start with at least

330 Ohms @ 1236hrs
690 Ohms @ 1310hrs
1425 Ohms @ 1410hrs
2142 Ohms @ 1510hrs
2768 Ohms @ 1630hrs
3100 Ohms @ 1730hrs

I have yet to back probe the pins to check voltage, but on the surface it would all suggest the ECT to be working correctly.

Interestingly large difference between measuring the sensor directly, and then again at the opposite end of the cable. Nearly half the resistance, perhaps due to multiple ground paths? Likewise interesting to see that just the cable is so high.

Feb 4th, 2020, 18:08	#35
CosmicBike Senior Member Last Online: May 5th, 2024 16:31 Join Date: Dec 2019 Location: Surrey	Numbers, interspersed with painting, dog walking and cooking. COLD (as in not started, ambient circa 10 degrees C) Sensor only, measured directly on sensor terminals: 9.04k Ohms All other measurements taken at pins 5 & 13 on ECU. Sensor connected: 4.57k Ohms Sensor disconnected: Open Loop (infinity Ohms) Sensor plug shorted: 860 Ohms And after re-connecting the ECU and battery, followed by a 14 mile drive to the dump and to fill with petrol. Temperature gauge just below mid-point when I returned to the driveway. Hot to start with at least 330 Ohms @ 1236hrs 690 Ohms @ 1310hrs 1425 Ohms @ 1410hrs 2142 Ohms @ 1510hrs 2768 Ohms @ 1630hrs 3100 Ohms @ 1730hrs I have yet to back probe the pins to check voltage, but on the surface it would all suggest the ECT to be working correctly. Interestingly large difference between measuring the sensor directly, and then again at the opposite end of the cable. Nearly half the resistance, perhaps due to multiple ground paths? Likewise interesting to see that just the cable is so high.