OBD Guide

P28B3

Cylinder 9 Ion Current Sense Circuit High

P28B3 is an OBD-II diagnostic trouble code meaning: Cylinder 9 Ion Current Sense Circuit High. Common causes: open or short circuit in the sensor circuit, ion current sensor malfunction. Estimated repair cost: $17–56.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Unstable engine operation
  • Increased fuel consumption
  • Reduced engine power
  • Check Engine Light Illuminates
  • Possible misfires

Causes

  • Open or short circuit in the sensor circuit
  • Ion current sensor malfunction
  • Wiring Harness Problems
  • Engine control module malfunction
  • Corrosion of contacts or connectors

How to Fix

  1. Check the integrity of the sensor circuit
  2. Inspect connectors and contacts for corrosion
  3. Check the resistance of the ion current sensor
  4. If necessary, replace the sensor or repair the wiring
  5. Reset the code and check if the error is returned

Related codes

Error P28B3 by Vehicle Brand

FAQ

What does the P28B3 code mean?

P28B3 is an OBD-II diagnostic trouble code that indicates: Cylinder 9 Ion Current Sense Circuit High

What causes a P28B3 error code?

The most common causes of P28B3 include: Open or short circuit in the sensor circuit; Ion current sensor malfunction; Wiring Harness Problems; Engine control module malfunction.

How do I fix a P28B3 diagnostic trouble code?

To fix P28B3: Check the integrity of the sensor circuit. Inspect connectors and contacts for corrosion. Check the resistance of the ion current sensor. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P28B3?

Yes, but get it checked soon

How much does it cost to fix P28B3?

The estimated repair cost for P28B3 is $17–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat