Yamaha FZ 25 2021 Supplementary Service Manual page 194

Fault code No.
Symptoms
Diagnostic code No.
Item and components and
Item
probable cause
1 Able/Unable to start with a self-
starter.
2 Discharged battery
3 Check the connection of the
battery terminals and lead.
4 Harness continuity.
SELF-DIAGNOSTIC FUNCTION AND
DIAGNOSTIC CODE TABLE
P1602
The ECU cannot record vehicle status (Throttle opening, O2FB learn-
ing value, etc.).
Repeat the main switch ON 
start with a self-starter  main
switch OFF twice.
Charge the battery.
If the battery cannot be
charged, replace the battery.
After charging the battery, per-
form the procedure in item 1
again.
Connect the battery terminals to
the lead so that the screws are
not loose and the terminals do
not come off.
Open or short circuit  Replace
the harness.
Between ECU and the battery
6-64
Actions
Cannot start with a self-starter
 Perform the procedure in item
2.
If you can start with a self-start-
er, check the condition of the
fault code in diagnostic mode of
the Yamaha diagnostic tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 6.
Cannot start with a self-starter
 Perform the procedure in item
3.
If you can start with a self-start-
er, check the condition of the
fault code in diagnostic mode of
the Yamaha diagnostic tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 6.
Repeat turning the main switch
ON  start with a self-starter 
main switch OFF twice, then
check the condition of the fault
code using the malfunction
mode of the Yamaha diagnostic
tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 4.
Repeat turning the main switch
ON  start with a self-starter 
main switch OFF twice, then
check the condition of the fault
code using the malfunction
mode of the Yamaha diagnostic
tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 5.
ELEC
Confirmation procedure after
actions
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