Honda Crf250l Service Manual

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PGM-FI SYSTEMMIL 8 BLINKS (TP SENSOR) 
Probable cause
 • Open circuit in Yellow/red wire between the sensorunit and ECM
 • Open or short circuit in Yellow wire between the sensor unit and ECM
 • Open circuit in Green/white wire between the sensor
unit and ECM
 • Faulty sensor unit
 • Faulty ECM
1. Sensor Unit Power Line Inspection
Check the sensor unit power line inspection (page
4-8).
Is the sensor unit power line normal?
YES – GO TO STEP 2.
NO – Replace or repair the abnormal...

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PGM-FI SYSTEM
3. TP Sensor Output Line Open Circuit InspectionCheck for continuity between the ECM 33P (Black)
connector [1] and sensor unit 5P connector [2] of
the wire side.
Is there continuity?
YES – GO TO STEP 4.
NO – Open circuit in Yellow wire
4. TP Sensor Resistance Inspection Connect the sensor unit 5P connector.
Check that the resistance  varies in accordance with
the throttle operation at the ECM 33P (Black)
connector of the wire side.
Is the resistance normal?
YES –...

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PGM-FI SYSTEM
1. Sensor Unit Power Line InspectionCheck the sensor unit power line inspection (page
4-8).
Is the sensor unit power line normal?
YES – GO TO STEP 2.
NO – Replace or repair the abnormal circuit.
2. IAT Sensor Output Voltage Inspection Turn the ignition switch OFF.
Connect the ECM 33P (Black) connector.
Disconnect the sensor unit 5P connector [1] (page
4-44).
Turn the ignition switch ON and engine stop switch
.
Measure the voltage at the sensor unit 5P connector
of...

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PGM-FI SYSTEM
5. IAT Sensor Resistance InspectionTurn the ignition switch OFF.
Connect the sensor unit 5P connector.
Disconnect the ECM 33P (Black) connector [1].
Measure the resistance at the ECM 33P (Black)
connector of the wire side.
Is the resistance within 1.13 – 1.88 k Ω (20°C/
68°F)?
YES – Replace the ECM with a known good one,
and recheck.
NO – Faulty sensor unit (IAT sensor)
MIL 11 BLINKS (VS SENSOR)
Before starting the inspection, check for loose or poor contact on the...

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PGM-FI SYSTEM
2. VS Sensor Signal Line InspectionTurn the ignition switch OFF.
Disconnect the ECM 33P (Black) connector [1].
Turn the ignition switch ON and engine stop switch
.
Measure the voltage at the ECM 33P (Black)
connector of the wire side.
Slowly turn the rear wheel by hand.
There should be 0 V to 5 V pulse voltage.
Is there 0 – 5 V pulse voltage?
YES – Replace the ECM with a known good one
and recheck.
NO – Open or short circuit in White/red wire.
MIL 12 BLINKS...

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PGM-FI SYSTEM
1. Injector Input Voltage InspectionTurn the ignition switch OFF.
Disconnect the injector 2P (Gray) connector [1]
(page 7-14).
Turn the ignition switch ON and engine stop switch
.
Measure the voltage between the injector 2P (Gray)
connector of the wire side and ground.
Does the standard voltage exist?
YES – GO TO STEP 2.
NO – Open circuit in Black/blue wire
2. Injector Signal Line Short Circuit Inspection Turn the ignition switch OFF.
Disconnect the ECM 33P (Black)...

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PGM-FI SYSTEMMIL 21 BLINKS (O
2 SENSOR)
Before starting the inspection, check for loose or poor contact on the O2 sensor 1P (Black) connector or O2sensor cap and recheck the MIL blinking.
Probable cause
 • Open or short circuit in Black/white or Black wirebetween the O
2 sensor and ECM
 • Faulty O2 sensor
 • Faulty ECM
1. O
2 Sensor System Inspection
Start the engine and warm up the engine up to
coolant temperature is 80°C/176°F.
Test-ride the motorcycl e and recheck the MIL...

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PGM-FI SYSTEM
3. O2 Sensor Open Circuit Inspection
Check for continuity between the ECM 33P (Black)
connector [1] and O
2 sensor cap terminal [2] of the
wire side.
Is there continuity?
YES – GO TO STEP 4.
NO – Open circuit in Black or Black/white wire
4. O
2 Sensor Inspection
Replace the O
2 sensor with a known good one
(page 4-47).
Connect the ECM 33P (Black) connector.
Start the engine and warm up the engine up to
coolant temperature is 80°C/176°F.
Test-ride the motorcycle and...

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PGM-FI SYSTEM
1. IACV Resistance InspectionTurn the ignition switch OFF.
Disconnect the IACV 4P (Black) connector [1] (page
7-15).
Measure the resistance at the IACV side connector.
Is the resistance within 110 – 150  Ω (25°C/77°F)?
YES – GO TO STEP 2.
NO – Faulty IACV
2. IACV Short Circuit Inspection Disconnect the ECM 33P (Black) connector (page
4-50).
Check for continuity between the IACV 4P (Black)
connector [1] of the wire side and ground.
Is there continuity?
YES –  • Short...

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PGM-FI SYSTEM
MIL 54 BLINKS (BANK ANGLE 
SENSOR)
Before starting the inspection, check for loose or poor contact on the bank angle  sensor 2P connector and
recheck the MIL blinking.
Probable cause
 • Open circuit in Black/blue wire between the engine
stop switch and bank angle sensor
 • Open or short circuit in Red/blue wire between the bank angle sensor and ECM
 • Faulty bank angle sensor
 • Faulty ECM
1. Bank Angle Sensor Input Voltage Inspection
Turn the ignition switch OFF....