Yamaha YZF-R125 Service Manual: Checking the condition of the bulbs

Yamaha YZF-R125 Service Manual / Electrical system / Electrical components / Checking the bulbs and bulb sockets / Checking the condition of the bulbs

The following procedure applies to all of the bulbs.

1. Remove:

Bulb

WARNING

Since the headlight bulbs get extremely hot, keep flammable products and your hands away from them until they have cooled down.

CAUTION:

Be sure to hold the socket firmly when removing the bulb. Never pull the lead, otherwise it may be pulled out of the terminal in the coupler.
Avoid touching the glass part of a headlight bulb to keep it free from oil, otherwise the transparency of the glass, the life of the bulb, and the luminous flux will be adversely affected. If the headlight bulb gets soiled, thoroughly clean it with a cloth moistened with alcohol or lacquer thinner.

2. Check:

Bulb (for continuity) (with the pocket tester) No continuity Replace.

NOTE:

Before checking for continuity, set the pocket tester to "0" and to the " × 1" range.

a. Connect the positive tester probe to terminal "1" and the negative tester probe to terminal "2", and check the continuity.

b. Connect the positive tester probe to terminal "1" and the negative tester probe to terminal "3", and check the continuity.

c. If either of the readings indicate no continuity, replace the bulb.

Types of bulbs

The bulbs used on this vehicle are shown in the illustration. Bulbs "a" and "b" are used for the headlights and usually use a bulb holder that must be detached before removing the bulb. The m ...

Checking the condition of the bulb sockets

The following procedure applies to all of the bulb sockets. 1. Check: Bulb socket (for continuity) (with the pocket tester) No continuity Replace. NOTE: Check each bulb socket for continui ...

Other materials:

Adjusting the drive chain slack
NOTE: The drive chain slack must be checked at the tightest point on the chain. CAUTION:A drive chain that is too tight will overload the engine and other vital parts, and one that is too loose can skip and damage the swingarm or cause an accident. Therefore, keep the drive ...

Checking the crankshaft position sensor
1. Disconnect: Crankshaft position sensor coupler (from the wire harness) 2. Check: Crankshaft position sensor resistance Out of specification Replace the crankshaft position sensor/stator assembly. a. Connect the pocket tester ( × 100) to the crankshaft position sensor c ...

Checking the cylinder head breather hose
1. Remove: Left side panel Refer to "GENERAL CHASSIS" on page 4-1. 2. Check: Cylinder head breather hose "1" Cracks/damage → Replace. Loose connection → Connect properly. CAUTION:Make sure the cylinder head breather hose is routed correctly. ...