Yamaha YZF-R125 Service Manual: Checking the ignition coil

Yamaha YZF-R125 Service Manual / Electrical system / Electrical components / Checking the ignition coil

1. Check:

Primary coil resistance Out of specification Replace.

a. Disconnect the ignition coil connectors from the ignition coil terminals.

b. Connect the pocket tester ( × 1)
to the ignition coil as shown.

Positive tester probe
red/white "1"

Negative tester probe
orange "2"

Checking the ignition coil

c. Measure the primary coil resistance.

2. Check:

Secondary coil resistance Out of specification Replace.

a. Disconnect the spark plug cap from the ignition coil.

b. Connect the pocket tester ( ×
1k) to the ignition coil as shown.

Positive tester probe
orange "1"
Negative tester probe
spark plug lead "2"

Checking the ignition coil

c. Measure the secondary coil resistance.

Checking the spark plug cap

1. Check: Spark plug cap resistance Out of specification Replace. a. Remove the spark plug cap from the spark plug lead. b. Connect the pocket tester ( × 1k) to the spark plug cap as ...

Checking the ignition spark gap

1. Check: Ignition spark gap Out of specification Perform the ignition system troubleshooting, starting with step 5. Refer to "TROUBLESHOOTING" on page 8-3. NOTE: If the ignition spark gap ...

Other materials:

Checking the lean angle sensor
1. Remove: Lean angle sensor 2. Check: Lean angle sensor output voltage Out of specification Replace. a. Connect the lean angle sensor to the wire harness. b. Connect the pocket tester (DC 20 V) to the lean angle sensor coupler as shown. Positive tester probe yellow/green "1" Neg ...

Overheating
Engine 1. Clogged coolant passages Cylinder head and piston Heavy carbon buildup 2. Engine oil Incorrect oil level Incorrect oil viscosity Inferior oil quality Cooling system 1. Coolant Low coolant level 2. Radiator Damaged or leaking radiator Faulty radiator cap ...

Removing the rear brake master cylinder
NOTE: Before removing the rear brake master cylinder, drain the brake fluid from the entire brake system. 1. Disconnect: Rear brake light switch coupler 2. Loosen: Rear brake light switch "1" 3. Remove: Rear brake master cylinder bolts Rear brake master cylinder 4. Remove: ...