OBD2 Car ScannerWhat does C1855 mean?
C1855 stands for Acceleration Position Sensor Conflict. A chassis module has found a fault in a system like ABS, traction or stability control, steering or suspension.
Chassis codes cover the ABS, traction control, steering and suspension. When the car's computer sees a reading outside its normal range, it stores this code and may turn on a warning light on the dashboard.
Common causes
- Faulty or dirty wheel speed sensor
- Damaged sensor wiring
- Low brake fluid
- Faulty ABS pump or module
What to do
- Read all stored and pending codes with a scanner. Several codes together often point to one cause.
- Note the freeze frame data (speed, temperature, load) recorded when the code was set.
- Inspect the wiring and connectors of the part named in the code for damage, corrosion or looseness.
- Fix the most likely and cheapest cause first, then clear the code and drive to see if it comes back.
Read this code from your own car
Plug in a cheap ELM327 adapter and the app shows every fault code, what it means and how to fix it.
Frequently asked questions
What does C1855 mean?
C1855 means “Acceleration Position Sensor Conflict”. It belongs to the chassis system group: A chassis module has found a fault in a system like ABS, traction or stability control, steering or suspension.
Is it safe to drive with C1855?
Avoid driving long distances. This kind of fault can cause damage or affect safety, so get it checked as soon as possible.
How do I clear C1855?
Fix the cause, then clear the code with an OBD2 scanner or app. If the fault is still there, the code will come back.
Related codes
- C1851Air Suspension Warning Lamp Circuit Open
- C1852Air Suspension Warning Lamp Circuit Short To Battery
- C1853Air Suspension Warning Lamp Circuit Short To Ground
- C1854Motor Temperature Out of Range
- C1856Traction Motor Encoder circuit Failure
- C1859PRNDL Input #2 Circuit Failure
- C1860PRNDL Input #3 Circuit Failure
- C1861PRNDL Input #4 Circuit Failure
Code meanings can vary by manufacturer. This page is general guidance, not a repair manual. Always confirm the cause before replacing parts.