P1272: Cylinder #2 Injector Circuit Open (High to Low Side)
The P1272 code indicates an open circuit between the high and low sides of the fuel injector for cylinder #2. This means the injector's internal coil or wiring is broken, preventing the injector from opening. The ECM detects this by monitoring the current flow; an open circuit results in no current, triggering the code. This is a specific injector circuit fault, not a general misfire.
01. Most Common Causes
- Open circuit in injector #2 wiring harness
- Faulty fuel injector #2 (internal coil open)
- Corroded or damaged connector at injector #2
- ECM internal fault (rare)
02. Symptoms You Will Notice
- Check Engine Light on
- Engine misfire at idle or under load
- Rough running and loss of power
- Increased fuel consumption
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect injector #2 connector and wiring for damage or corrosion.
Step 3: Use a multimeter to measure resistance between injector #2 terminals (should be 12-16 ohms). If open (OL), replace injector.
Step 4: Check for 12V at injector #2 with key on; if missing, trace wiring back to ECM.
Step 5: Perform a continuity test from injector connector to ECM; repair open circuit if found.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not recommended. Driving with a misfire can damage the catalytic converter and cause poor performance.
How much does it cost to fix?▼
Typically $150-$400, including diagnostic time and replacement of the injector if needed.