Honda Crf250l Service Manual

4-22
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PGM-FI SYSTEM
3. Injector Signal Line Short Circuit InspectionTurn the ignition switch OFF.
Check for continuity between the injector 2P (Gray)
connector [1] of wire side and ground.
Is there continuity?
YES – Short circuit in Pink/white wire
NO – GO TO STEP 4.
4. Injector Resistance Inspection Measure the resistance between the injector 2P
(Gray) connector [1] terminals.
Is the resistance within 11 – 13  Ω (20°C/68°F)?
YES – GO TO STEP 5.
NO – Faulty injector
5. Injector Signal...

4-23
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PGM-FI SYSTEM
DTC 21 (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 wire
between the O
2 sensor and ECM
 • Faulty O2 sensor
 • Faulty ECM
DTC 21-1 (O
2 Sensor)
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 motorcycle and...

4-24
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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°C).
Test-ride the motorcycle...

4-25
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PGM-FI SYSTEM
1. Recheck DTCErase the DTC’s (page 4-5).
Turn the ignition switch ON and engine stop switch
.
Check the IACV with the HDS pocket tester.
Is the DTC 29-1 indicated?
YES – GO TO STEP 2.
NO –  • Intermittent failure
 • Loose or poor contact on the IACV 4P
(Black) connector
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...

4-26
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PGM-FI SYSTEM
4. 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 – Replace the ECM with a known good one
and recheck.
NO – Faulty IACV
DTC 33-2 (EEPROM)
1. Recheck DTC
Erase the DTC’s (page 4-5).
Turn the ignition switch ON and engine stop switch
.
Recheck the ECM EEPROM.
Is the DTC 33-2 indicated?
YES –...

4-27
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PGM-FI SYSTEM
DTC 54-1 (BANK ANGLE SENSOR LOW VOLTAGE)
1. Recheck DTC
Erase the DTC’s (page 4-5).
Turn the ignition switch ON and engine stop switch
.
Check the bank angle sensor with the HDS pocket
tester.
Is the DTC 54-1 indicated?
YES – GO TO STEP 2.
NO – Intermittent failure
2. Bank Angle Sensor Input Voltage Inspection Turn the ignition switch OFF.
Disconnect the bank angle sensor 2P connector [1]
(page 4-48).
Turn the ignition switch ON and engine stop switch
.
Measure the...

4-28
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PGM-FI SYSTEM
5. Bank Angle Sensor InspectionReplace the bank angle sensor with a known good
one (page 4-48).
Connect the bank angle sensor 2P connector and
ECM 33P (Black) connector.
Erase the DTC’s (page 4-5).
Turn the ignition switch ON and engine stop switch
.
Check the bank angle sensor with the HDS pocket
tester.
Is DTC 54-2 indicated?
YES – Replace the ECM with a known good one
and recheck.
NO – Faulty original the bank angle sensor.
DTC 54-2 (BANK ANGLE SEN SOR HIGH...

4-29
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PGM-FI SYSTEM
MIL TROUBLESHOOTING
MIL 1 BLINK (MAP SENSOR) 
Probable cause
 • Open circuit in Yellow/red wire between the sensorunit and ECM
 • Open or short circuit in Light green/black 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 –...

4-30
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PGM-FI SYSTEM
3. MAP Sensor Output Line Short CircuitInspection
Turn the ignition switch OFF.
Disconnect the ECM 33P (Black) connector.
Check for continuity between the sensor unit 5P
connector [1] terminal of the wire side and ground.
Is there continuity?
YES – Short circuit in Light green/black wire
NO – GO TO STEP 4.
4. MAP Sensor Output Line Open Circuit Inspection
Check for continuity between the ECM 33P (Black)
connector [1] and sensor unit 5P connector [2] of
the wire...

4-31
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PGM-FI SYSTEM
1. ECT Sensor Input Voltage InspectionTurn the ignition switch OFF.
Disconnect the ECT sensor 3P connector [1] (page
4-46).
Turn the ignition switch ON and engine stop switch
.
Measure the voltage at the ECT sensor 3P
connector of the wire side and ground.
Is the voltage within 4.75 – 5.25 V?
YES – GO TO STEP 3.
NO – GO TO STEP 2.
2. ECT Sensor Short Circuit Inspection Turn the ignition switch OFF.
Disconnect the ECM 33P (Black) connector (page
4-50).
Check for...