C0238Speed Wheel-to-Wheel Mismatch
- Generic OBD-II code · Chassis
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- C0238 does not appear in the publicly available J2012 code lists. GM uses it: the terminal-check bulletin PIP5094 for 2014 and older GM cars and light trucks names it as a chassis keyword, and AA1Car's table of GM ABS codes calls it Wheel Speed Mismatch, which fits the title. GM does not publish its setting rule for this number. A related GM test on the 2011 Saab 9-5 shows the principle: above 14 km/h, brake off and driving straight, a wheel reading more than 20 percent off the others is treated as a fault. Typical reasons are one tyre of a different size or pressure, a spare wheel, a damaged tone ring or a sensor with too much air gap. ABS and traction control are normally switched off until the next ignition cycle.
- What you may notice
- ABS and traction control warning lamps on
- ABS and traction control disabled for the rest of the trip
- Likely causes
- LikelyOne tyre with different size, wear or pressure, or a space-saver spare fitted
- PossibleCracked, corroded or wrong tone ring on one wheel
- PossibleWheel speed sensor loose or with excessive air gap, or worn wheel bearing
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.