Injector Circuit / Open - Cylinder 12
The P0212 code means the vehicle's onboard diagnostic system has detected: Injector Circuit / Open - Cylinder 12. This is a critical severity code.
- Keep driving?
- No — stop driving
- DIY difficulty
- hard
- Estimated cost
- $200 - $600 (fuel injector $100-$300; labor $150-$400)
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What Are the Symptoms of P0212?
- Check Engine Light on or flashing
- Cylinder 12 misfire causing rough running
- Power loss noticeable under acceleration
- Engine vibration and shaking
- Fuel smell from unburned fuel in exhaust
What Causes P0212? (Most Likely First)
- Failed fuel injector on cylinder 12 Very High
- Open or damaged wire in the injector circuit High
- Corroded or disconnected injector connector Moderate
- PCM injector driver failure Low
- High resistance in injector coil Low
Can I Still Drive with P0212?
No — stop driving. P0212 is rated critical severity. Continuing to drive in this state risks further damage — get it looked at before your next trip.
Frequently Asked Questions
Can I drive with code P0212?
No. A dead cylinder 12 sends unburned fuel into the exhaust system, which can destroy the catalytic converter. Have the vehicle towed and repaired.
Is cylinder 12 the last cylinder on a V12?
Yes. Cylinder 12 is the final cylinder on V12 engines. These are exclusively found on luxury and high-performance vehicles.
Should I take a V12 to a specialist for P0212?
Yes, V12 engines are complex and require specialized knowledge. A dealer or specialist mechanic familiar with your vehicle brand will have the diagnostic tools and experience to properly repair the injector circuit.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P0212?
-
Confirm cylinder 12 misfire with a scan tool.
-
Measure injector resistance on cylinder 12 (11-17 ohms typical).
-
Check for injector pulse at the connector using a noid light during cranking.
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Inspect wiring and connector for damage, corrosion, or breaks.
-
Swap the injector with another cylinder to isolate the fault.
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Which Vehicles Commonly Get P0212?
- 2003-2012 Ferrari 599 GTB (6.0L V12)
- 2005-2016 Mercedes-Benz S600 (5.5L V12 biturbo)
- 2008-2018 BMW 760Li (6.0L V12)
- 2010-2017 Aston Martin Rapide (6.0L V12)
- 2007-2015 Rolls-Royce Phantom (6.75L V12)
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