Yamaha YZF-R1S Service Manual page 377

Fault code No. 48
Used diagnostic code 56
Order Inspection operation item and probable
couse
1 Connected condition of connector
Inspect the coupler for any pins that
may have pulled out.
Check the locking condition of the
coupler
2 Open or short circuit in wire harness.
3 Defective sub-throttle servo motor.
Fault code No. 50
Used diagnostic code No. – –
Order Inspection operation item and probable
cause
1 Malfunction in ECU
FUEL INJECTION SYSTEM
Symptom Sub-throttle servo motor is stuck.
Operation item and countermeasure
If there is a malfunction repair it and
connect it securely.
Sub-throttle servo motor coupler
Main wire harness ECU coupler.
Repair or replace if there is an open
or short circuit.
Between motor coupler and ECU coupler.
Yellow / Red – Yellow / Red
Yellow / White – Yellow / White
Execute the diagnostic mode (Code No.56).
Replace if defective.
1. Disconnect the sub-throttle cables from the
Sub-throttle servomotor pulley.
2. Disconnect the sub-throttle servomotor coupler
from the wire harness.
3. Connect the battery leads to the sub-throttle
servomotor coupler as shown.
Positive battery terminal ! yellow / red
Negative battery terminal ! yellow/white
4. Check that the sub-throttle servomotor pulley
rotates several times.
CAUTION:
To prevent damaging the sub-throttle ser-
vomotor, perform this test within a few se-
conds of connecting the battery.
5. Does the sub-throttle servomotor pulley turn?
Symptom Faulty ECU memory. (When this malfunction is detected in the ECU, the fault
code number might not appear on the meter.)
Operation item and countermeasure
Replace the ECU.
7-33
FI
Reinstatement
method
Reinstated by
turning the
main switch
ON.
It takes 120
seconds at the
maximum
before the
original state
returns.
1
2
Reinstatement
method
Reinstated by
turning the
main switch
ON.