Honda Crf250l Service Manual

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PGM-FI SYSTEM
3. MAP Sensor System Inspection 2Turn the ignition switch OFF.
Disconnect the sensor unit 5P connector [1].
Connect the sensor unit 5P connector terminals at
the wire side with a jumper wire [2].
Turn the ignition switch ON and engine stop switch
.
Check the MAP sensor with the HDS pocket tester.
Is about 0 V indicated?
YES – Faulty sensor unit (MAP sensor)
NO – GO TO STEP 4.
4. MAP Sensor Output Line Open Circuit Inspection
Turn the ignition switch OFF.
Remove the jumper wire.
Disconnect the ECM 33P (Black) connector [1].
Check the continuity bet ween the ECM 33P (Black)
connector and sensor unit 5P connector [2] of the
wire side.
Is there continuity?
YES – Replace the ECM with a known good one
and recheck.
NO – Open circuit in Light green/black wire
DTC 7 (ECT SENSOR)
Before starting the inspection, check  for loose or poor contact on the ECT sensor 3P connector and recheck the
MIL blinking.
Probable cause
 • Open or short circuit in Yellow/blue wire between the
ECT sensor and ECM
 • Open circuit in Green/white wire between the ECT sensor and ECM
 • Faulty ECT sensor
 • Faulty ECM Connection:
Light green/black – Green/white
G/W
[1] Lg/Bl
[2]
Connection:
Light green/black – Light green/black
TOOL:
Test probe 07ZAJ-RDJA110Lg/Bl
[2][1]
Lg/Bl
Y/Bu
G/W
5 V
ECM
ECT SENSOR 
						

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PGM-FI SYSTEM
DTC 7-1 (ECT SENSOR LOW VOLTAGE)
1. ECT Sensor System InspectionTurn the ignition switch ON and engine stop switch
.
Check the ECT sensor with the HDS pocket tester.
Is about 0 V indicated?
YES – GO TO STEP 2.
NO – Intermittent failure
2. ECT Sensor Inspection Turn the ignition switch OFF.
Disconnect the ECT sensor 3P connector.
Turn the ignition switch ON and engine stop switch
.
Check the ECT sensor with the HDS pocket tester.
Is about 0 V indicated?
YES – GO TO STEP 4.
NO – GO TO STEP 3.
3. ECT Sensor Resistance Inspection Turn the ignition switch OFF.
Measure the resistance at the ECT sensor [1]
terminals.
Is the resistance within 2.3 – 2.6 k Ω (20°C/68°F)?
YES – Replace the ECM with a known good one
and recheck.
NO – Faulty ECT sensor
4. ECT Sensor Short Circuit Inspection Turn the ignition switch OFF.
Check for continuity between the ECT sensor 3P
connector [1] of the wire side and ground.
Is there continuity?
YES – Short circuit in Yellow/blue wire
NO – Replace the ECM with a known good one
and recheck.
Standard: 2.3 – 2.6 k Ω (20°C/68°F)
[1]
Connection: Yellow/blue – Ground
Y/Bu
[1] 
						

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PGM-FI SYSTEM
DTC 7-2 (ECT SENSOR HIGH VOLTAGE)
1. ECT Sensor System InspectionTurn the ignition switch ON and engine stop switch
.
Check the ECT sensor with the HDS pocket tester.
Is about 5 V indicated?
YES – GO TO STEP 2.
NO –  • Intermittent failure
 • Loose or poor contact on the ECT
sensor 3P connector
2. ECT Sensor Inspection Turn the ignition switch OFF.
Disconnect the ECT sensor 3P connector [1].
Connect the ECT sensor 3P connector terminals at
the wire side with a jumper wire [2].
Turn the ignition switch ON and engine stop switch
.
Check the ECT sensor with the HDS pocket tester.
Is about 0 V indicated?
YES – Inspect the ECT sensor (page 4-46).
NO – GO TO STEP 3.
3. ECT Sensor Open Circuit Inspection Turn the ignition switch OFF.
Remove the jumper wire.
Disconnect the ECM 33P (Black) connector [1].
Check the continuities between the ECM 33P
(Black) connector and ECT sensor 3P connector [2]
of the wire side.
Is there continuity?
YES – Replace the ECM with a known good one
and recheck.
NO –  • Open circuit in Yellow/blue wire
 • Open circuit in Green/white wire
Connection: Yellow/blue – Green/white
Y/Bu
[1]
G/W
[2]
Connection: Yellow/blue – Yellow/blue Green/white – Green/white
TOOL:
Test probe 07ZAJ-RDJA110
[2]
G/W
Y/Bu
[1]
G/W
Y/Bu 
						

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PGM-FI SYSTEM
DTC 8 (TP SENSOR) 
Probable cause
 • Open circuit in Yellow/red wire between the sensor unit 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
DTC 8-1 (TP SENSOR LOW VOLTAGE)
1. TP Sensor System Inspection
Turn the ignition switch ON and engine stop switch
.
Check the TP sensor with the HDS pocket tester
when the throttle fully closed.
Is about 0 V indicated?
YES –  • Intermittent failure
 • Loose or poor contact on the sensor
unit 5P connector
NO – GO TO STEP 2.
2. 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 3.
NO – Replace or repair the abnormal circuit.
3. TP Sensor Output Line Short Circuit Inspection Turn the ignition switch OFF.
Disconnect the sensor unit 5P connector [1].
Check for continuity between the sensor unit 5P
connector of the wire side and ground.
Is there continuity?
YES – Short circuit in Yellow wire
NO – GO TO STEP 4.
Y/R
G/W
5 V
ECM
SENSOR UNIT 
(TP SENSOR)
Y
Connection: Yellow – Ground Y
[1] 
						

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PGM-FI SYSTEM
4. TP Sensor Output Line Open Circuit InspectionDisconnect the ECM 33P (Black) connector [1].
Check for continuity between the ECM 33P (Black)
connector and sensor unit 5P connector [2] of the
wire side.
Is there continuity?
YES – GO TO STEP 5.
NO – Open circuit in Yellow wire
5. TP Sensor Inspection Replace the sensor unit with a known good one
(page 4-44).
Connect the sensor unit  5P and ECM 33P (Black)
connectors.
Erase the DTC’s (page 4-5).
Turn the ignition switch ON and engine stop switch
.
Check the TP sensor with the HDS pocket tester.
Is DTC 8-1 indicated?
YES – Replace the ECM with a known good one
and recheck.
NO – Faulty original sensor unit (TP sensor)
DTC 8-2 (TP SENSOR HIGH VOLTAGE)
1. TP Sensor System Inspection Turn the ignition switch ON and engine stop switch
.
Check the TP sensor with the HDS pocket tester.
Is about 5 V indicated?
YES – GO TO STEP 3.
NO – GO TO STEP 2.
2. TP Sensor Inspection Check that the TP sensor voltage increases
continuously when moving the throttle from fully
closed to fully opened using the data list menu of the
HDS pocket tester.
Is the voltage increase continuously?
YES – Intermittent failure
NO – Replace the TP sensor (sensor unit) with a
known good one and recheck.
Connection: Yellow – Yellow
TOOL:
Test probe
07ZAJ-RDJA110
Y
[1][2]Y 
						

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PGM-FI SYSTEM
3. TP Sensor Resistance InspectionTurn the ignition switch OFF.
Disconnect the ECM 33P (Black) connector [1].
Measure the resistance at the ECM 33P (Black)
connector of the wire side.
Is the resistance within 0.29 – 0.71  Ω?
YES – GO TO STEP 4.
NO – Faulty sensor unit (TP sensor)
4. TP Sensor Power Input Voltage Inspection Connect the ECM 33P (Black) connector.
Disconnect the sensor unit 5P connector [1].
Turn the ignition switch ON and engine stop switch
.
Measure the voltage at the sensor unit 5P connector
of the wire side.
Is the voltage within 4.75 – 5.25 V?
YES – Replace the ECM with a known good one,
and recheck.
NO –  • Open circuit in Green/white wire
 • Open circuit in Yellow/red wire
DTC 9 (IAT SENSOR)
Probable cause
 • Open or short circuit in Gray/blue wire between the
sensor unit and ECM
 • Open circuit in Green/white wire between the sensor unit and ECM
 • Faulty sensor unit
 • Faulty ECM Connection: Yellow – Green/white
Standard: 0.29 
– 0.71 Ω (20°C/68°F)
[1] G/W
Y
Connection: Yellow/red (+) – Green/white (–)
Standard: 4.75 – 5.25 VY/R G/W
[1]
Gr/Bu
G/W
5 V
ECM
SENSOR UNIT 
(IAT SENSOR) 
						

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PGM-FI SYSTEM
DTC 9-1 (IAT SENSOR LOW VOLTAGE)
1. IAT Sensor System InspectionTurn the ignition switch ON and engine stop switch
.
Check the IAT sensor with  the HDS pocket tester.
Is about 0 V indicated?
YES – GO TO STEP 2.
NO – Intermittent failure
2. IAT Sensor Inspection Turn the ignition switch OFF.
Disconnect the sensor unit 5P connector.
Turn the ignition switch ON and engine stop switch
.
Check the IAT sensor with  the HDS pocket tester.
Is about 0 V indicated?
YES – GO TO STEP 3.
NO – Faulty sensor unit (IAT sensor)
3. IAT Sensor Voltage Input Line Short Circuit Inspection
Check for continuity between the sensor unit 5P
connector [1] of the wire side and ground.
Is there continuity?
YES – Short circuit in Gray/blue wire
NO – Replace the ECM with a known good one,
and recheck.
DTC 9-2 (IAT SENSOR HIGH VOLTAGE)
1. IAT Sensor System Inspection Turn the ignition switch ON and engine stop switch
.
Check the IAT sensor with  the HDS pocket tester.
Is about 5 V indicated?
YES – GO TO STEP 2.
NO –  • Intermittent failure
 • Loose or poor contact on the sensor
unit 5P connector
2. 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 3.
NO – Replace or repair the abnormal circuit.
Connection: Gray/blue – Ground
Gr/Bu
[1] 
						

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PGM-FI SYSTEM
3. IAT Sensor InspectionTurn the ignition switch OFF.
Disconnect the sensor unit 5P connector [1].
Connect the IAT sensor terminals at the wire side
with a jumper wire [2].
Turn the ignition switch ON and engine stop switch
.
Check the IAT sensor with the HDS pocket tester.
Is about 0 V indicated?
YES – Faulty sensor unit (IAT sensor)
NO – GO TO STEP 4.
4. IAT Sensor Voltage Input Line Open Circuit Inspection
Turn the ignition switch OFF.
Disconnect the ECM 33P (Black) connector [1].
Check for continuity between the ECM 33P (Black)
connector and sensor unit 5P connector [2] of the
wire side.
Is there continuity?
YES – Replace the ECM with a known good one
and recheck.
NO – Open circuit in Gray/blue wire
DTC 11 (VS SENSOR)
Before starting the inspection, check for loose or poor contact on the VS sensor 3P (Blue) connector and
recheck the MIL blinking.
Probable cause
 • Open or short circuit in Pink or White/red wire
between the VS sensor and ECM
 • Faulty VS sensor
 • Faulty ECM Connection: Gray/blue – Green/white
G/W
[1]
Gr/Bu
[2]
Connection: Gray/blue – Gray/blue 
TOOL:
Test probe
07ZAJ-RDJA110
Gr/Bu
[1][2] Gr/Bu
G/Bl
Bl/R
ECM
VS SENSOR
To SPEEDOMETER
W/RW/R
G
Bl
P 
						

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PGM-FI SYSTEM
DTC 11-1 (VS SENSOR)
1. VS Sensor System InspectionErase the DTC’s (page 4-5).
Test ride the motorcycle.
Stop the engine.
Turn the ignition switch ON and engine stop switch
.
Check the VS sensor with the HDS.
Is DTC 11
–1 indicated?
YES – GO TO STEP 2.
NO –  • Intermittent failure
 • Loose or poor contact on the VS sensor
3P (Blue) connector
2. Speedometer Inspection Inspect the speedometer (page 20-5).
Is the speedometer normal?
YES – GO TO STEP 3.
NO – Replace or repair the abnormal circuit.
3. VS Sensor Signal Line Inspection Turn 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.
Connection: White/red (+) – Ground (–)
TOOL:
Test probe 07ZAJ-RDJA110
W/R
[1] 
						

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PGM-FI SYSTEM
DTC 12 (INJECTOR)
Before starting the inspection, check for loose or poor  contact on the injector 2P (Gray) connector and recheck
the MIL blinking.
Probable cause
 • Open circuit in Black/blue wire between the engine
stop switch and injector
 • Open or short circuit in Pink/white wire between the
injector and ECM
 • Faulty injector
 • Faulty ECM
DTC 12-1 (INJECTOR)
1. Injector System Inspection
Erase the DTC’s (page 4-5).
Turn the ignition switch ON and engine stop switch
.
Start the engine and check the injector with the HDS
pocket tester.
Is the DTC 12-1 indicated?
YES – GO TO STEP 2.
NO –  • Intermittent failure
 • Loose or poor contact on the injector
2P (Gray) connector
2. Injector Input Voltage Inspection Turn the ignition switch OFF.
Disconnect the injector 2P (Gray) connector [1].
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 3.
NO – Open or short circuit in Black/blue wire
Bl/Bu
ECM
INJECTOR
From ENGINE 
STOP SWITCH
P/W
Connection: Black/blue (+) – Ground (–)
Standard: Battery voltage
Bl/Bu
[1]