OBD Guide

B0120

Fluid Reservoir Level Sensor E

B0120 is an OBD-II diagnostic trouble code meaning: Fluid Reservoir Level Sensor E. Common causes: open or short circuit in the sensor circuit, sensor contamination. Estimated repair cost: $11–56.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$11–56 (est.)

Symptoms

  • Check engine light is on
  • False fluid level readings
  • No low fluid warnings

Causes

  • Open or short circuit in the sensor circuit
  • Sensor contamination
  • Mechanical damage to the float
  • Tank failure
  • Wiring Harness Problems

How to Fix

  1. Check the fluid level in the corresponding reservoir
  2. Visually inspect the sensor and circuit for damage
  3. Check sensor resistance
  4. Clean or replace sensor if necessary
  5. Check the integrity of the wiring harness

Related codes

Error B0120 by Vehicle Brand

FAQ

What does the B0120 code mean?

B0120 is an OBD-II diagnostic trouble code that indicates: Fluid Reservoir Level Sensor E

What causes a B0120 error code?

The most common causes of B0120 include: Open or short circuit in the sensor circuit; Sensor contamination; Mechanical damage to the float; Tank failure.

How do I fix a B0120 diagnostic trouble code?

To fix B0120: Check the fluid level in the corresponding reservoir. Visually inspect the sensor and circuit for damage. Check sensor resistance. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with B0120?

Limited driving only, diagnose soon

How much does it cost to fix B0120?

The estimated repair cost for B0120 is $11–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat