Cylinder #5 High to Low Side Short
Code P1265 indicates a short circuit between the high and low sides of the ignition coil or injector circuit for cylinder #5. This typically means the coil or injector driver circuit has failed, causing a direct electrical short that can prevent proper spark or fuel delivery. The issue may be internal to the coil/injector or in the wiring harness.
01. Most Common Causes
- Faulty ignition coil on cylinder #5
- Shorted wiring harness between PCM and coil/injector
- Failed PCM driver for cylinder #5
02. Symptoms You Will Notice
- Misfire on cylinder #5
- Check Engine Light illuminated
- Rough idle or hesitation
- Possible no-start condition
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Swap ignition coil from cylinder #5 with another cylinder and see if code follows.
Step 3: If code stays on #5, inspect wiring harness for shorts or damage.
Step 4: Test continuity and resistance of coil/injector circuit; if OK, suspect PCM failure.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, driving with a short can damage the PCM or cause a fire. It's best to tow to a shop.
How much does it cost to fix?▼
Typically $50-$150 for a coil replacement, but wiring repairs or PCM replacement can cost more.