Yamaha Apex RX10PA 2011 Supplementary Service Manual page 235

Fault
Symptom
code No.
No signals are received from
the ECU within the specified
Er-2
signal time.
Data from the ECU cannot be
received correctly.
Er-3
Non-registered data has been
received from the meter.
Er-4
FUEL INJECTION SYSTEM
Probable cause of malfunction
• Coupler defective between speedometer unit – ECU.
• Open or short circuit in wire harness.
• Malfunction in speedometer unit.
• Malfunction in ECU.
• Coupler defective between speedometer unit – ECU.
• Open or short circuit in wire harness.
• Malfunction in speedometer unit.
• Malfunction in ECU.
• Coupler defective between speedometer unit – ECU.
• Open or short circuit in wire harness.
• Malfunction in speedometer unit.
• Malfunction in ECU.
100
FI
Diagnostic
code No.
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