OBD Guide

P3109

Cylinder 3 High-Pressure Fuel Injector Low Side Circuit Low

P3109 is an OBD-II diagnostic trouble code meaning: Cylinder 3 High-Pressure Fuel Injector Low Side Circuit Low. Common causes: short circuit in injector control circuit, malfunction of the fuel injector of cylinder 3. Estimated repair cost: $28–167.

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$28–167 (est.)

Symptoms

  • Misfire in cylinder 3
  • Loss of engine power
  • Increased fuel consumption
  • Check Engine Light Is On
  • Rough engine idling

Causes

  • Short circuit in injector control circuit
  • Malfunction of the fuel injector of cylinder 3
  • Damage to the wiring to the injector
  • Problems with the engine control unit (ECU)
  • Corrosion of contacts or connectors

How to Fix

  1. Check the resistance of the injector of cylinder 3
  2. Inspect the injector wiring and connectors for damage.
  3. Check injector control circuit for short circuit
  4. If necessary, replace the fuel injector
  5. Update engine control unit software (if available)

Related codes

FAQ

What does the P3109 code mean?

P3109 is an OBD-II diagnostic trouble code that indicates: Cylinder 3 High-Pressure Fuel Injector Low Side Circuit Low

What causes a P3109 error code?

The most common causes of P3109 include: Short circuit in injector control circuit; Malfunction of the fuel injector of cylinder 3; Damage to the wiring to the injector; Problems with the engine control unit (ECU).

How do I fix a P3109 diagnostic trouble code?

To fix P3109: Check the resistance of the injector of cylinder 3. Inspect the injector wiring and connectors for damage.. Check injector control circuit for short circuit. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P3109?

Do not drive — repair immediately

How much does it cost to fix P3109?

The estimated repair cost for P3109 is $28–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat