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BF135A•BF150A
5-75
5. ECT sensor 1 check
-1. Turn the ignition switch OFF and disconnect the 2P
connector of the ECT sensor 1.
-2. Measure the resistance between the No. 1 and the No.
2 terminals of the ECT sensor 1 side 2P connector.
Is there the resistance corresponding to the engine
coolant temperature?
YES –
Substitute a known-good ECM and recheck.
NO –
Replace the ECT sensor 1.
• TP Sensor Troubleshooting
MIL blinks 7 times.
1. Symptom reproduction test
-1. Reset the ECM.
-2. Turn the ignition switch OFF and connect the test har-
ness.
Hold the sensor connector connected.
-3. Turn the ignition switch ON.
-4. Measure the voltage between the B-7 terminal (+) and
the A-2 terminal (–) of the test harness.
Is the measured voltage 0.08 – 4.92V?
YES –
Temporary failure (Disappeared)
NO –
Perform "2. TP sensor power supply line open
circuit check".
2. TP sensor power supply line open circuit check
-1. Turn the ignition switch ON.
Measure the voltage
between the No. 3 (Brown/White) terminal of the TP
sensor harness side 3P connector and the engine
ground.
Is the measured voltage 4.75 – 5.25V?
YES –
Perform "3. TP sensor signal line open circuit
check".
NO –
Repair open in the wire between the TP sen-
sor and the ECM.
RESIST
ANCE
ECT SENSOR 1 SIDE
2P CONNECTOR
VIEWED FROM THE TERMINAL SIDE
TP SENSOR HARNESS SIDE
3P CONNECTOR
VIEWED FROM THE TERMINAL SIDE
ENGINE COOLANT TEMPERATURE
A-2
B-7
VCC2
(BROWN/WHITE)