Honda CRF450R 2009 Service Manual page 162

FUEL SYSTEM (PGM-FI)
6·30
DTC 8-1 (TP SENSOR LOW VOLTAGE)
Before starting the inspection, check for loose or poor
contact on the TP sensor 3P (Blue) connector and ECM
33P connector, then recheck the DI G.
1. TP Sensor System Inspection
Connect the 12 V battery ("ECM" selector switch is
ON).
- '09:
page
6-19
- After '09: page 6-19
Check the TP sensor with the MCS when the throttle
is fully closed.
Is about 0 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
Mes.
Does the voltage Increase continuously?
YES - Intermittent failure
NO - Faulty TP sensor
3. TP Sensor Input Voltage Inspection
Tum the "ECM" selector switch OFF.
Disconnect the TP sensor 3P (Blue) connector.
Tum the "ECM" selector switch ON.
Measure the voltage at the wire side.
Connection: Red/yellow (+) - Green/red (- )
Is the voltage withIn 4.75 - 5.25 V?
YES - GO TO STEP
5.
NO - GO TO STEP 4 .
4.
TP Sensor Circuit Inspection
Tum the "ECM" selector switch OFF .
Disconnect the ECM 33P (Black) connector.
Check for continuity at the Red/yellow wire between
the TP sensor 3P (Blue) connector and ECM 33P
(Black) connector.
Connection: 14 - Red/yellow
TOOL:
Test probe, 2 pack
07ZAJ·RDJA 110
Is there continuity?
YES - Replace the ECM wi th a known good one.
3P (BLUE) CONNECTOR
(Wire sideJfemale terminals)
e
3P (BLUE) CONNECTOR
(Wire side/female terminals)
RfY
14
Q
and recheck. 33P (BLACK) CONNECTOR
NO - Open circuit in Red/yellow wire (Wire sidelfemale terminals)