Honda Crf250l Service Manual

4-2
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PGM-FI SYSTEM
PGM-FI SYSTEMSERVICE INFORMATION
GENERAL
 • A faulty PGM-FI system is often related to poorly connected or corroded connectors. Check those connections before
proceeding.
 • When disassembling the PGM-FI syst em parts, note the location of the O-rings. Replace them wi th new ones upon reassembly.
 • Use a digital tester for PGM-FI system inspection.
 • The following color codes are used throughout this section.
PGM-FI SYSTEM LOCATION
Bu = Blue G = Green Lb = Light...

4-3
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PGM-FI SYSTEM
PGM-FI SYSTEM DIAGRAM
(1)(8) (12)
(9) (7)
30
K-LINE
IACV1A
IACV2A
(21)
(29)
IAT SENSOR
ECT SENSOR
O
2 SENSOR
MAP SENSOR
SENSOR UNIT
CKP SENSOR
27 PB 25 SSTAND
UP
DOWN 29 NLSW
12 PCP
23 PCM8
FLR
TW-IND
5THL
14 TA
24 TW
3 6 VCC 4SG 1
IGP
16
INJ 19
FA N C
9 PG1 10 PG2 2 LG O2
TP SENSOR FUEL PUMP UNIT
FUEL
PUMP
RELAY
SPEEDOMETER
VS SENSOR MIL
HIGH COOLANT
TEMPERATURE INDICATOR
FA N
CONTRO
LRELAY
INJECTOR
IGNITION COIL
SCS CONNECTOR
IACV
26 BA
11
IGPLS
28
EX-AI
PAIR...

4-4
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PGM-FI SYSTEM
PGM-FI TROUBLESHOOTING INFORMATION
GENERAL TROUBLESHOOTING
Intermittent Failure
The term intermittent failure means a system may have had a failure, but it checks OK now. If the MIL does not come on, check
for poor contact or loose pins at all connectors related to the  circuit that of the troubleshooting. If the MIL was on, but then went out,
the original problem may be intermittent.
Opens and Shorts
Opens and Shorts are common electrical  terms. An open is a break...

4-5
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PGM-FI SYSTEM
HDS POCKET TESTER INFORMATION
 • The HDS pocket tester can readout the DTC,  freeze data, current data and other ECM condition.
How to connect the HDS pocket tester
Turn the ignition switch OFF.
Remove the dummy connector [1] from the DLC [2].
Connect the HDS pocket tester to the DLC.
Turn the ignition switch ON and engine stop switch   check the DTC and
freeze data.
Freeze data indicates the engine conditions when the first malfunction was
detected.
ECM reset
The...

4-6
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PGM-FI SYSTEMCIRCUIT INSPECTION
INSPECTION AT ECM CONNECTOR
 • Always clean around and keep any foreign material away from the ECM 33P (Black) connector before disconnecting it.
 • A faulty PGM-FI system is often rela ted to poorly connected or corroded
terminals. Check those connections before proceeding.
 • In testing at ECM 33P (Black) connector (wire harness side) terminal, always use the test probe [1]. Inse rt the test probe into the connector
terminal, then attach th e...

4-7
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PGM-FI SYSTEM
DTC INDEX
DTC 
(MIL 
blinks) Function Failure Symptom/Fail-safe function Refer 
to 
(DTC)  Refer 
to 
(MIL) 
1-1 (1) MAP sensor circuit low voltage (less than 0.195 V)
 • MAP sensor or its circuit malfunction  • Engine operates normally
 • Pre-program value: 525 mmHg/
700 hPa 4-10
4-29
1-2 (1) MAP sensor circuit high voltage (more than 3.848 V)
 • Loose or poor contact of the sensor unit 
connector
 • MAP sensor or its circuit malfunction  • Engine operates normally...

4-8
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PGM-FI SYSTEM
SENSOR UNIT POWER LINE 
INSPECTION
BEFORE DTC TROUBLESHOOTING
 • When the DTC displays 1-1, 1-2, 8-1, 8-2, 9-1 and 9-
2, check the following before DTC troubleshooting.
 • Before starting the inspection, check for loose or  poor contact on the sensor unit 5P connector and ECM
33P (Black) connector.
Probable cause
 • Open circuit in Yellow/red wire between the sensor unit and ECM
 • Open circuit in Green/white wire between the sensor unit and ECM
 • Faulty ECM
1....

4-9
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PGM-FI SYSTEM
 • Open circuit in Green/white wire
BEFORE MIL TROUBLESHOOTING
 • When the MIL blinks 1, 8 and 9 times, check thefollowing before MIL troubleshooting.
 • Before starting the inspection, check for loose or  poor contact on the sensor unit 5P connector and ECM
33P (Black) connector.
Probable cause
 • Open circuit in Yellow/red wire between the sensor unit and ECM
 • Open circuit in Green/white wire between the sensor unit and ECM
 • Faulty ECM
1. Sensor Unit Power...

4-10
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PGM-FI SYSTEM
DTC TROUBLESHOOTING
DTC 1 (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
DTC 1-1 (MAP SENSOR LOW VOLTAGE)
1. MAP sensor system inspection
Turn the ignition switch ON and engine stop switch
.
Check the MAP sensor with the HDS pocket...

4-11
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PGM-FI SYSTEM
4. 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 5.
5. MAP Sensor Inspection Replace the sensor unit with a known good one
(page 4-44).
Erase the DTC’s (page 4-5).
Turn the ignition switch OFF.
Connect the sensor...