What it means
The control module detected a high electrical signal in the cylinder 12 injector B circuit. This indicates an electrical circuit condition; it does not by itself establish injector flow or cylinder fuel balance.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The control module monitors the electrical signal in the injector B circuit for cylinder 12. This code sets when that signal is higher than expected, which may be caused by a wire shorted to voltage, a connector fault, or an injector electrical problem; it does not by itself indicate injector flow or fuel balance.
Common causes
Most likely first.
- Short to voltage in wiring
- Damaged or corroded connector
- Injector electrical fault
Symptoms
- Check-engine light on
- Rough running or misfire
- Reduced engine power
- Increased fuel consumption
How to diagnose it
- Record freeze-frame data and check for companion injector or misfire codes to see when the cylinder 12 circuit fault was detected.
- Inspect the cylinder 12 injector B connector and harness for damaged insulation, corrosion, loose terminals, or wiring touching a power feed.
- Check scan-tool data against the manufacturer's diagnostic information to verify the high-signal report for injector B on cylinder 12.
- Safely isolate the circuit as directed by the manufacturer, then test for a short to voltage and poor terminal contact.
- If the circuit checks out, test the cylinder 12 injector B electrical characteristics to the manufacturer's specification.
Common fixes
- Repair any cylinder 12 injector B wire shorted to voltage.
- Clean or repair the injector B connector if its terminals are corroded, loose, or damaged.
- Replace the cylinder 12 injector B only if its electrical test identifies an internal fault.
Can I keep driving?
Gentle, limited driving may be possible if the engine runs normally. Avoid hard acceleration, and stop if it misfires severely or the warning light flashes because unburned fuel can damage the catalytic converter.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.