P20CD

What it means

Exhaust Aftertreatment Fuel Injector A Control Circuit Low: the control-circuit voltage is below the expected range. This injector doses fuel into the exhaust to raise temperature for diesel particulate-filter regeneration; it does not fuel the engine.

Is it safe to drive?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

• Short to ground

  high

  One of the most commonly reported causes for this code — check this first.

• Connector pins corroded - high contact resistance

  low

  Less common, but worth ruling out after the more likely causes.

• Harness chafing through insulation

  low

  Less common, but worth ruling out after the more likely causes.

Related help

• Full P20CD diagnosis, causes & costs
• How to read check engine light codes
• Is it safe to drive with the light on?