B2105 Code: Meaning, Symptoms, Causes & Fix

Overview

Code B2105 indicates a fault in Throttle Position Input Out of Range Low, typically within air metering and throttle control.

Symptoms

poor throttle response
occasional limp mode
surging or unstable idle

Common causes

Signal pulled low by short-to-ground affecting throttle position input out of range low
High circuit resistance
Connector pin damage/corrosion or harness stress near related components

How to diagnose B2105

Confirm B2105 and capture freeze-frame data with a professional scan tool.
Inspect wiring, connectors, and grounds related to throttle position input out of range low for obvious defects.
Compare live data against expected lower threshold and verify ground/reference circuits.
Check for related DTCs to identify the root-cause chain before replacing parts.
After repair, clear codes and confirm readiness monitors complete without recurrence.

Severity of code B2105

Moderate: This code is moderate severity: the vehicle may still operate, but fault progression can increase repair cost over time.

Can you drive with B2105?

Most vehicles can be driven short-term with B2105, but postpone heavy load/highway driving until repaired.

If the warning lamp is flashing or drivability/safety is affected, avoid driving and diagnose immediately.

How to fix it (step-by-step)

Repair obvious wiring/connector faults first to prevent repeat parts replacement.
Address the root fault mode (low) in the throttle position input out of range low circuit/system.
Apply the required relearn/adaptation procedure if specified by service information.
Road-test and verify B2105 remains cleared under the conditions that originally set the code.

Fix options

Replace failed sensor if signal remains low.
Repair connector resistance issues.
Clear DTCs and verify with live data and completed drive cycle.

Typical repair cost

$180-$900

Common mistakes when diagnosing B2105

Replacing parts without verifying voltage, ground, and signal integrity first.
Ignoring related stored/pending codes that indicate upstream faults.
Skipping post-repair verification drive cycle and readiness checks.

B2105 in common vehicles

B2105 appears across makes such as Mazda, Subaru, Lexus, Jeep. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.

Frequently asked questions

What causes B2105?

B2105 is commonly set by low faults affecting throttle position input out of range low.

How much does it cost to fix B2105?

For B2105, repair costs are typically $180-$900 depending on exact root cause, labor rates, and part quality.

Can I clear B2105 without repair?

You can clear B2105 temporarily, but the code usually returns until the underlying fault is corrected.