YAMAHA WR 250F 2008 Owners Manual

7-20
SIGNALING SYSTEM
SIGNALING SYSTEM
INSPECTION STEPS
If the speedometer will not operate, use the following inspection steps.
*1 marked: Refer to "CHECKING AND CHARGIN G THE BATTERY" section in the CHAPTER 3.
• Remove the following parts before inspection.
1. Headlight
• Use the following special tools in this inspection.
*1 Check battery. No good→Recharge or replace.
OK ↓
Check each coupler and wire connection. No good →Repair or replace.
OK ↓
Check multi-function display. (Input voltage) No good →Replace wire harness.
OK ↓
Check multi-function displa y. (Output voltage) No good →Replace multi-function display.
OK ↓
Check speed sensor. No good→Replace.
Pocket tester:
YU-3112-C/90890-03112

7-21
SIGNALING SYSTEM
CHECKING THE COUPLERS AND
LEADS CONNECTION
1. Check:• Couplers and leads connection
Rust/dust/looseness/short-circuit
→ Repair or replace.
CHECKING THE MULTI-FUNCTION
DISPLAY INPUT VOLTAGE
1. Disconnect the multi-function dis- play coupler.
2. Set the main switch to "ON".
3. Measure:
• Multi-function display input volt-age
Out of specification →Replace
wire harness.
Make sure that a short-circuit does
not develop between the terminals
because it may cause damage to
electrical components.
CHECKING THE MULTI-FUNCTION
DISPLAY OUTPUT VOLTAGE
1. Disconnect the multi-function dis- play coupler.
2. Set the main switch to "ON".
3. Measure: • Multi-function display output volt-age
Out of specification →Replace
multi-function display.
Make sure that a short-circuit does
not develop between the terminals
because it may cause damage to
electrical components.
CHECKING THE SPEED SENSOR
OUTPUT VOLTAGE
1. Insert the thin electric conductors
"1" (lead) into the speed sensor
coupler "2", as shown, and con-
nect the tester to them.
• Do not insert the electric conduc-tors more than required because
it may reduce the waterproof
function of the coupler.
• Make sure that a short-circuit does not develop between the
terminals because it may cause
damage to electrical compo-
nents.
2. Set the main switch to "ON".
3. Measure:
• Speed sensor output voltageOutput voltage not correct →Re-
place the speed sensor.
Measurement steps:
a. Elevate the front wheel and slowly
rotate it.
b. Measure the voltage (DCV) of white lead and black lead. With
each full rotation of the front
wheel, the voltage reading should
cycle from 0.6 V to 4.8 V to 0.6 V
to 4.8 V.
Tester (+) lead →Brown lead "1"
Tester (-) lead →Black lead "2"
Multi-func- tion dis-
play input voltage Tester se-
lector posi- tion
10 V or more DCV-20
Tester (+) lead →Red lead "1"
Tester (-) lead →Black/White lead
"2"
Multi-func-tion dis-
play output
voltage Tester se-
lector posi- tion
4.5 V or more DCV-20
Tester (+) lead
→White lead "3"
Tester (-) lead →Black lead "4"

PRINTED\bIN\bJAPAN(E\f
PRINTED\bON\bRECYCLED\b\OPAPER\bYAMAHA\bMOTOR\bCO.,\bLTD.
2500\b SHINGAI\b IWATA\b SHIZUOKA\b JAPAN