Body, generic

B011C Fluid Reservoir Level Sensor A

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B011C is the first of six fluid reservoir level sensors, A to F. J2012 does not say which reservoir each letter belongs to; the neighbouring codes deal with washing windows, cameras and other sensors, so washer tanks are the obvious candidates. The classic design pairs a magnet-bearing float with a reed switch: falling fluid lowers the float, and the contact flips. The application US20040200278A1 shows such a unit pushed through a rubber grommet in the tank side wall. FCA parts tip 9003109 adds a practical failure: a float that has turned out of its anti-rotation guides keeps reporting low fluid in a full bottle. No maker documents B011C publicly; the effect is a wrong or missing low-fluid warning.

Likely causes

Float jammed, rotated out of its guide or soaked with fluid
Reed contact inside the sensor broken or welded
Leaking grommet letting fluid reach the plug, corroded terminals

Symptoms

  • Low-fluid warning stays on although the reservoir is full
  • No warning at all when the reservoir runs empty

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–150
Time0.3–1.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fluid reservoir level sensor asensor wiring

Related codes

B011DB011EB011FB0120B0121

References: patents.google.com, static.nhtsa.gov.