TROUBLESHOOTING
9-1
EAS28450
TROUBLESHOOTING
EAS28460
GENERAL INFORMATION
TIP
The following guide for troubleshooting does not
cover all the possible causes of trouble. It should
be helpful, however, as a guide to basic trouble-
shooting. Refer to the relative procedure in this
manual for checks, adjustments, and replace-
ment of parts.
EAS28480
STARTING FAILURE/HARD STARTING
Engine
1. Cylinder and cylinder head
• Loose spark plug
• Loose cylinder head or cylinder
• Damaged cylinder head gasket
• Damaged cylinder gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Improperly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
2. Piston and piston ring(s)
• Improperly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
3. Air filter
• Improperly installed air filter
• Clogged air filter element
4. Crankcase and crankshaft
• Improperly assembled crankcase
• Seized crankshaft
Fuel system
1. Fuel tank
• Empty fuel tank
• Clogged fuel tank cap breather hole
• Deteriorated or contaminated fuel
• Clogged or damaged fuel hose
2. Fuel pump
• Faulty fuel pump
• Clogged fuel pump filter
3. Throttle body
• Deteriorated or contaminated fuel
• Sucked-in air
Electrical system
1. Battery
• Discharged battery
• Faulty battery
2. Fuse(s)
• Blown, damaged or incorrect fuse
• Improperly installed fuse
3. Spark plug
• Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
4. Ignition coil
• Cracked or broken ignition coil body
• Broken or shorted primary or secondary coils
• Faulty spark plug lead
5. Ignition system
• Faulty ECU
• Faulty crankshaft position sensor
• Broken generator rotor woodruff key
6. Switches and wiring
• Faulty main switch
• Broken or shorted wiring
• Faulty front, rear or both brake light switches
• Faulty start switch
• Faulty sidestand switch
• Improperly grounded circuit
• Loose connections
7. Starting system
• Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cut-off relay
• Faulty starter clutch
EAS28500
INCORRECT ENGINE IDLING SPEED
Engine
1. Cylinder and cylinder head
• Incorrect valve clearance
• Damaged valve train components
2. Air filter
• Clogged air filter element
Fuel system
1. Throttle body
• Damaged or loose throttle body joint
• Improper throttle cable free play
Electrical system
1. Battery
• Discharged battery
Summary of Contents for XMAX 125
Page 1: ...SERVICE MANUAL 2010 37P F8197 E0 YP125R YP250R ...
Page 6: ......
Page 8: ......
Page 28: ...SPECIAL TOOLS 1 19 ...
Page 30: ...COOLING SYSTEM DIAGRAMS YP250R 2 73 CABLE ROUTING YP250R 2 75 ...
Page 31: ......
Page 55: ...LUBRICATION POINTS AND LUBRICANT TYPES YP125R 2 24 ...
Page 62: ...CABLE ROUTING YP125R 2 31 Front fork front view A 1 1 1 1 2 2 2 3 4 5 6 7 ...
Page 66: ...CABLE ROUTING YP125R 2 35 Engine right side view A 7 3 2 2 2 1 3 4 5 6 7 ...
Page 70: ...CABLE ROUTING YP125R 2 39 Engine left side view 2 1 3 4 A 3 ...
Page 72: ...CABLE ROUTING YP125R 2 41 Handlebar top view A 1 2 3 4 4 5 6 7 8 9 10 11 12 13 14 15 16 17 ...
Page 76: ...CABLE ROUTING YP125R 2 45 Tail brake light top view 2 1 3 4 B A 1 5 6 ...
Page 103: ...LUBRICATION POINTS AND LUBRICANT TYPES YP250R 2 72 ...
Page 108: ...CABLE ROUTING YP250R 2 77 Front fork front view 1 1 2 3 4 5 6 7 1 2 A 1 2 ...
Page 112: ...CABLE ROUTING YP250R 2 81 Engine right side view A 7 3 2 2 2 1 3 4 5 6 7 8 B ...
Page 116: ...CABLE ROUTING YP250R 2 85 Engine left side view 2 1 3 4 5 6 B A 3 7 ...
Page 118: ...CABLE ROUTING YP250R 2 87 Handlebar top view A 1 2 3 4 4 5 6 7 8 8 9 10 11 12 13 14 15 16 17 ...
Page 122: ...CABLE ROUTING YP250R 2 91 Tail brake light top view 2 1 3 4 B A 1 5 6 8 7 ...
Page 124: ...CABLE ROUTING YP250R 2 93 ...
Page 127: ......
Page 172: ...ELECTRICAL SYSTEM 3 45 ...
Page 175: ......
Page 240: ...REAR SHOCK ABSORBER ASSEMBLIES AND SWINGARM 4 65 ...
Page 245: ......
Page 305: ...CRANKSHAFT YP125R 5 60 a 1 ...
Page 366: ...CRANKSHAFT YP250R 5 121 ...
Page 394: ...THROTTLE BODY 7 11 ...
Page 397: ......
Page 411: ...CHARGING SYSTEM 8 14 ...
Page 423: ...SIGNALING SYSTEM 8 26 ...
Page 427: ...COOLING SYSTEM 8 30 ...
Page 453: ...FUEL INJECTION SYSTEM 8 56 ...
Page 457: ...FUEL PUMP SYSTEM 8 60 ...
Page 466: ...IMMOBILIZER SYSTEM 8 69 a Light on b Light off ...
Page 467: ...IMMOBILIZER SYSTEM 8 70 ...
Page 495: ......
Page 496: ...YAMAHA MOTOR ESPAÑA S A ...