OBD-II code · Powertrain (generic)
P0609 Control Module VSS Output B
A fault is detected on the secondary vehicle speed signal output (VSS B) that the ECU sends to other modules (instrument cluster, ABS, transmission). Output level inconsistent with the internal speed value.
Is it safe to drive with P0609?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOutput driver fault
Symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–3 h
- Emissions test
- Usually unaffected
- Parts involved
- Control Module Vss Output B
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.