What does code P1686 mean on Honda vehicles?
The ECU detects a low input signal on FI Signal B of the automatic transaxle.
OBD-II Code Honda
P1686 — Honda — Automatic Transaxle FI Signal B Low Input
The ECU detects a low input signal on FI Signal B of the automatic transaxle.
Common symptoms
- Limp mode activation
Possible causes
- Open circuit
- damaged wiring
- high resistance
Initial recommendation
Perform automatic transaxle diagnostics and repair FI Signal B circuit.
Safety notice
This information is for guidance only. Brand-specific codes may vary by model, year, engine, transmission and vehicle configuration. It does not replace a physical inspection or diagnosis by a qualified mechanic. If the vehicle is unsafe to operate, avoid driving it and seek professional inspection.
Analyze this code with MecaOBD
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