P1275: Cylinder #5 Injector Circuit Open
The P1275 code indicates an open circuit between the high and low sides of the fuel injector for cylinder #5. This means the injector's electrical circuit is broken, preventing the injector from opening and delivering fuel. The engine control module (ECM) detects this fault when the expected current flow through the injector is not present. This can cause a misfire, rough idle, and reduced engine performance.
01. Most Common Causes
- Faulty fuel injector on cylinder #5
- Open or shorted wiring in the injector circuit
- Corroded or damaged connector at the injector
- ECM internal fault (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire on cylinder #5
- Rough idle or hesitation during acceleration
- Decreased fuel economy and power loss
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm P1275 and check for related codes.
Step 2: Visually inspect the injector connector and wiring for damage or corrosion.
Step 3: Measure resistance across injector #5 terminals (should be 11-17 ohms).
Step 4: Check for voltage at the injector connector with key on (should be battery voltage on one pin).
Step 5: Perform a noid light test to confirm injector pulse from ECM.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with a misfire can damage the catalytic converter and cause further engine issues.
How much does it cost to fix?▼
Typically $150-$400, including parts and labor. Injector replacement is around $100-$200, plus diagnostic time.