C1237 (blink 29) on Toyota Passo (KGC10): Sensor rotor missing teeth
Short answer: C1237 means “Sensor rotor missing teeth”. The car’s computer has found a fault in the ABS system and turns on the ABS warning light. First check: follow manual section procedure for this code.
- Code
- C1237 · blink 29
- System
- ABS
- Dashboard light
- ABS warning light
- Also sold as
- Daihatsu Boon, Daihatsu Sirion (M300)
- Applies to
- M300/M301 export; JDM Boon/Passo 1st gen by platform
- Confidence
- high (factory chart); description parsing medium
- Source
- carmanualsclub.com
Symptoms and when it is set
- Warning lamp per chart (see page)
Likely causes
- Sensor rotor missing teeth
What to check, in order
- Follow manual section procedure for this code
Related on this car
Clearing the code does not fix the fault. If it comes back, the problem is still there. For brakes, airbags and steering, see a trained mechanic.

