Severity High
P202D

Reductant Leakage Detected

📅 Last reviewed: July 2026
What does the P202D code mean?

The P202D code indicates that the engine control module (ECM) has detected a leak in the reductant (diesel exhaust fluid, DEF) system. This can be caused by a faulty DEF injector, a cracked DEF tank, loose connections, or a malfunctioning DEF pump. The system monitors the pressure and flow of DEF; when a leak is detected, the ECM sets this code to alert the driver and may limit vehicle performance to reduce emissions.

High
Severity
$50-$150
Typical Cost
High
Frequency

1. Most Common Causes

2. Symptoms You Will Notice

3. Step-by-Step Diagnosis

1

Step 1: Use a scan tool to confirm P202D and check for related codes.

2

Step 2: Visually inspect the DEF system for leaks, cracks, or loose connections.

3

Step 3: Perform a pressure test on the DEF system to locate the leak.

4

Step 4: Check the DEF injector for proper operation and replace if necessary.

4. Frequently Asked Questions

Is it safe to drive with this code?

It is not recommended to drive long distances as the vehicle may enter limp mode, reducing power and potentially causing further damage. Additionally, continued driving may lead to non-compliance with emissions regulations.

How much does it cost to fix?

The cost to fix a DEF leak typically ranges from $50 to $150 for diagnosis and minor repairs like tightening connections, but can be higher if parts like the injector or tank need replacement.

5. Commonly Affected Makes

This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.

6. Related Codes

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