Honda CBR125R Owner's Manual page 127

3. ECT Sensor Resistance Inspection
Turn the ignition switch OFF.
Measure the resistance at the ECT sensor termi-
nals.
Connection: Yellow/blue – Green/orange
Standard: 2.3 – 2.6 kΩ (20°C/68°F)
Is the resistance within 2.3 – 2.6 k Ω (20 ° C/68 ° F)?
YES – GO TO STEP 4.
NO – Faulty ECT sensor
4. ECT Sensor Open Circuit Inspection
Connect the ECM test harness to ECM 33P con-
nector (page 5-13).
Check the continuities between the ECM test har-
ness and ECT 3P sensor connector of the wire
side.
Connection: 24 – Yellow/blue
4 – Green/orange
Are there continuities?
YES – GO TO STEP 5.
NO – • Open circuit in Yellow/blue wire
• Open circuit in Green/orange wire
5. ECT Sensor Output Voltage Inspection
Connect the ECT sensor 3P connector.
Turn the ignition switch ON (and engine stop
switch " ": CM and U type).
Measure the voltage at the ECM test harness ter-
minals.
Connection: 24 (+) – 4 (–)
Standard: 2.7 – 3.1 V (20°C/68°F)
Is the voltage within 2.7 – 3.1 V (20 ° C/68 ° F)?
YES – • Loose or poor contact on the ECM
connector
• Intermittent failure
NO – Replace the ECM with a known good
one, and recheck.
FUEL SYSTEM (PGM-FI)
G/O
ECT SENSOR (Sensor side/male terminals)
ECT SENSOR 3P CONNECTOR
(Wire side/female terminals)
G/O
Y/Bu
(24)
(24) (4)
Y/Bu
(4)
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