Reductant Pump Control Circuit/Open
The P208A code indicates an open or malfunction in the reductant pump control circuit, which is part of the Selective Catalytic Reduction (SCR) system. This pump delivers diesel exhaust fluid (DEF) to the exhaust stream to reduce NOx emissions. An open circuit means the powertrain control module (PCM) detects a lack of continuity or voltage in the pump's electrical circuit, preventing proper DEF injection. This can lead to increased emissions and potential derate of engine power.
1. Most Common Causes
- Blown fuse or faulty relay for the reductant pump
- Open or shorted wiring in the pump control circuit
- Faulty reductant pump motor
- Corroded or loose electrical connectors at the pump
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or derate mode
- Increased diesel exhaust fluid consumption or no DEF usage
- Possible white smoke from exhaust
3. Step-by-Step Diagnosis
Step 1: Scan for codes and verify P208A is present. Check for related codes like P208B or P20EE.
Step 2: Inspect the reductant pump fuse and relay; replace if blown.
Step 3: Visually inspect wiring and connectors for damage, corrosion, or loose connections.
Step 4: Test pump motor resistance and voltage supply using a multimeter; compare to manufacturer specs.
Step 5: If circuit is intact, replace the reductant pump assembly.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances. The vehicle may enter limp mode, reducing power, and continued driving can cause damage to the SCR system or lead to non-compliance with emissions regulations.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, including parts and labor. The reductant pump itself costs $100-$250, plus diagnostic time and labor.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.