KTM 250 EXC-F Owner's Manual page 114

22 BLINK CODE
Blink code FI warning lamp (MIL)
Error level condition
45 FI warning lamp (MIL) flashes 4x long, 5x short
EXC‑F EU, EXC‑F Factory Edition, EXC‑F BR, EXC‑F Six Days
Lambda sensor heater cylinder 1, sensor 1 - short circuit to ground or open circuit
EXC‑F EU, EXC‑F Factory Edition, EXC‑F BR, EXC‑F Six Days
Lambda sensor heater cylinder 1, sensor 1 - input signal too high
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