Cylinder 1 High to Low Side Short
Findings, check these first
- Shorted cylinder 1 injector solenoid
- Chafed under-cover harness shorting
- Valve cover gasket connector short
- Oil-soaked wiring breaking down
- IDM driver fault
Standard procedure
- Buzz test and note cylinder 1 response
- Inspect the under-cover harness for chafing
- Test injector resistance for internal shorts
- Check the gasket connector
- Repair wiring or replace the injector
Code lookup
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Sources and review
Review: checked against the recorded source material.
- OBDII.pro: P1261 Ford definition
live reference page (obdii.pro)
Supports: Ford-family meaning for P1261: Cylinder #1 High To Low Side Short
Fetched directly. obdii.pro is a publisher independent of the engine-codes family.
- P1261 FORD Code: Meaning, Causes, and Symptoms | OBD2 Codes
live reference page (obd2-codes.co)
Supports: Ford meaning for P1261: Cylinder #1 High To Low Side Short
Fetched directly. obd2-codes.co phrasing matches the engine-codes family, so it counts as one publisher.
Last updated 2026-09-06.
Report a correction for P1261. Include your vehicle, the issue and a source if you have one.
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