Severity High
P0273

Cylinder 5 Injector Circuit Low

📅 Last reviewed: July 2026
What does the P0273 code mean?

The P0273 code indicates that the Engine Control Module (ECM) has detected a low voltage or current condition in the electrical circuit for the fuel injector on cylinder 5. This typically means the injector's resistance is too low, there is a short to ground, or the injector driver circuit is malfunctioning. The ECM monitors the injector circuit for proper voltage and current flow; when the signal falls below a specified threshold, it sets this code. This can lead to incomplete fuel delivery, causing misfires and reduced engine performance.

High
Severity
$150-$400
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 the code and check for related codes (e.g., P0205 for injector circuit).

2

Step 2: Visually inspect the injector connector and wiring for damage, corrosion, or shorts.

3

Step 3: Measure the resistance of the cylinder 5 injector with a multimeter; compare to manufacturer specs (typically 12-16 ohms).

4

Step 4: Perform a continuity test on the injector circuit from the ECM to the injector connector.

5

Step 5: If wiring and injector are good, test the ECM output with a noid light or oscilloscope to verify the driver signal.

4. Frequently Asked Questions

Is it safe to drive with this code?

It is not recommended to drive long distances as the misfire can damage the catalytic converter and cause further engine issues. Short trips to a repair shop are acceptable if the engine is not running rough.

How much does it cost to fix?

The cost typically ranges from $150 to $400, including parts and labor. A single injector replacement is around $100-$200, plus diagnostic time.

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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