P1396 Code: Meaning, Symptoms, Causes & Fix

Overview

Symptoms

• reduced performance
• increased fuel use
• check engine light

Common causes

• Sensor output out of expected lower range affecting glow plug monitor fault (bank #2)
• Signal pulled low by short-to-ground
• Connector pin damage/corrosion or harness stress near related components

How to diagnose P1396

1. Confirm P1396 and capture freeze-frame data with a professional scan tool.
2. Inspect wiring, connectors, and grounds related to glow plug monitor fault (bank #2) for obvious defects.
3. Compare live data against expected lower threshold and verify ground/reference circuits.
4. Check for related DTCs to identify the root-cause chain before replacing parts.
5. After repair, clear codes and confirm readiness monitors complete without recurrence.

Severity of code P1396

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

Can you drive with P1396?

Most vehicles can be driven short-term with P1396, 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)

1. Repair obvious wiring/connector faults first to prevent repeat parts replacement.
2. Address the root fault mode (low) in the glow plug monitor fault (bank #2) circuit/system.
3. Apply the required relearn/adaptation procedure if specified by service information.
4. Road-test and verify P1396 remains cleared under the conditions that originally set the code.

Fix options

• Replace failed sensor if signal remains low.
• Verify ground path and signal integrity.
• Clear DTCs and verify with live data and completed drive cycle.

Typical repair cost

$200-$900

Common mistakes when diagnosing P1396

• 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.

P1396 in common vehicles

P1396 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 P1396?

P1396 is commonly set by low faults affecting glow plug monitor fault (bank #2).

How much does it cost to fix P1396?

For P1396, repair costs are typically $200-$900 depending on exact root cause, labor rates, and part quality.

Can I clear P1396 without repair?

You can clear P1396 temporarily, but the code usually returns until the underlying fault is corrected.

Helpful tools

• Estimate repair cost
• Decode your VIN
• Calculate fuel cost