P1302 Code: Meaning, Symptoms, Causes & Fix

Overview

P1302 is triggered when monitoring logic identifies an issue with Boost Calibration Low affecting air metering and throttle control.

Symptoms

surging or unstable idle
engine feels underpowered
poor throttle response

Common causes

Signal pulled low by short-to-ground affecting boost calibration low
Sensor output out of expected lower range
Connector pin damage/corrosion or harness stress near related components

How to diagnose P1302

Confirm P1302 and capture freeze-frame data with a professional scan tool.
Inspect wiring, connectors, and grounds related to boost calibration 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 P1302

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

Can you drive with P1302?

Most vehicles can be driven short-term with P1302, 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 boost calibration low circuit/system.
Apply the required relearn/adaptation procedure if specified by service information.
Road-test and verify P1302 remains cleared under the conditions that originally set the code.

Fix options

Verify ground path and signal integrity.
Repair connector resistance issues.
Clear DTCs and verify with live data and completed drive cycle.

Typical repair cost

$180-$900

Common mistakes when diagnosing P1302

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.

P1302 in common vehicles

P1302 appears across makes such as BMW, Mercedes-Benz, Audi, Volvo. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.

Frequently asked questions

What causes P1302?

P1302 is commonly set by low faults affecting boost calibration low.

How much does it cost to fix P1302?

For P1302, repair costs are typically $180-$900 depending on exact root cause, labor rates, and part quality.

Can I clear P1302 without repair?

You can clear P1302 temporarily, but the code usually returns until the underlying fault is corrected.