Yamaha RST90GTY, Service Manual, Page: 141 / 299

63
FI
FUEL INJECTION SYSTEM
Fault code No. 26 Symptom
Intake air pressure sensor 2 (cylinder #1): hose system malfunction
(clogged or detached hose).
Diagnostic code No. d:04 (intake air pressure sensor 2 (cylinder #1))
Order Item/components and probable cause Check or maintenance job Reinstatement
method
1 Intake air pressure sensor 2 (cylinder #1)
hose is detached, clogged, kinked, or
pinched. Repair or replace the intake air pressure sensor 2
(cylinder #1) hose. Starting the
engine and
operating it at
idle.
2 Intake air pressure sensor 2 (cylinder #1)
malfunction at intermediate electrical
potential. Check and repair the connection.
Replace it if there is a malfunction.
3 Connections
• Intake air pressure sensor 2 (cylinder #1)
coupler
• Wire harness ECU coupler
Check the couplers for any pins that may have
pulled out.
Check the locking condition of the couplers.
If there is a malfunction, repair it and connect the
coupler securely.
4 Defective intake air pressure sensor 2
(cylinder #1). Execute the diagnostic mode (code No. d:04).
Replace if defective.
Refer to “Fault code No. 25”.
Fault code No. 30 Symptom Engine stops when an oil pressure drop is detected.
Diagnostic code No. – –
Order Item/components and probable cause Check or maintenance job Reinstatement
method
1 Oil pressure dropped. Place the snowmobile on a level surface, and
then check the oil pressure after warming up the
engine.
Refer to “ENGINE OIL REPLACEMENT” in
CHAPTER 2. Starting the
engine and
operating it at
idle.
2 Short circuit in oil pressure switch lead
and/or oil pressure switch sub-lead. Disconnect the ECU coupler, and then use the
circuit tester to check for continuity between the
engine ground and the oil pressure switch cou-
pler (yellow/green).
Repair or replace if there is no continuity.
3 Defective oil pressure switch. Start the engine, warm it up for 1 minute, and
then use the circuit tester to check for continuity
between the oil pressure switch coupler (yellow/
green) and the switch body.
Replace if there is continuity.