Drive with caution — fix soon.
This code means the transmission control computer detected a problem with the output (vehicle) speed sensor circuit, which measures how fast the transmission output shaft is spinning. It's frequently caused by a failed sensor, damaged wiring, or a poor connector, and sometimes by debris on the sensor. Repairs are often straightforward, typically replacing the sensor or fixing the wiring.
$100 – $500
Varies by vehicle and root cause.
Short trips are often possible, but be careful. Without a correct speed signal the transmission may shift roughly or go into limp mode, and your speedometer may be unreliable, so get it repaired soon.
It's usually one of the more affordable transmission codes. Replacing the speed sensor and any wiring repair typically runs about $100 to $500, depending on the sensor's location and labor.
It's moderately serious. It often comes down to a simple sensor, but the faulty signal can cause erratic shifting and limp mode, so it shouldn't be left unaddressed.
On many vehicles the output speed sensor also feeds the speedometer and cruise control, so when it fails you may see a jumpy or dead speedometer along with the shifting problems.