AutoCodes – Generic – P12C0

P12C0 Code - Cylinder 7 Injection Timing Advance

Quick Answer

The Engine Control Module (ECM) has the ability to learn injector timing performance. Common causes include Contaminated or improper fuel quality, Worn base engine components or differences in cylinder compression, Faulty Fuel Injector. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P12C0 indicates Cylinder 7 Injection Timing Advance.
Common causes: Common causes include Contaminated or improper fuel quality, Worn base engine components or differences in cylinder compression, Faulty Fuel Injector.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 3,404

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 11, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P12C0 Description

The Engine Control Module (ECM) has the ability to learn injector timing performance. With the engine at operating temperature and in closed throttle decel mode, the ECM will pulse each injector individually and measure the changes in rotational speed of the crankshaft using the input from the Crankshaft Position Sensor (CPS). The ECM will run this diagnostic under three different fuel rail pressures for each injector. The ECM will adjust the timing of fuel delivered by each injector to obtain the desired RPM increase. The ECM stores the injector timing value required to increase the crankshaft speed by the desired RPM. If the ECM cannot control an increase in RPM for a given injector the appropriate code will set for that injector.

OBDII Code P12C0 - Cylinder 7 Injection Timing Advance - AutoCodes.com — P12C0 Code - Cylinder 7 Injection Timing Advance

What does this mean?

What are the Possible Causes of the DTC P12C0?

Contaminated or improper fuel quality
Worn base engine components or differences in cylinder compression
Faulty Fuel Injector
Fuel Injector harness is open or shorted
Fuel Injector circuit poor electrical connection

How to Fix the DTC P12C0?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P12C0 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P12C0 code?

Need more information on how to fix the P12C0 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P12C0 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P12C0 Chevrolet — Cylinder 7 Injection Timing Advance
P12C0 GMC — Cylinder 7 Injection Timing Advance

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P12C0 Code

1. What does the OBDII code P12C0 mean?

P12C0 indicates an issue with the timing advance for cylinder 7's fuel injection, meaning the Engine Control Module (ECM) has detected abnormal timing.

2. What are the common symptoms of the P12C0 code?

Symptoms may include rough idling, reduced engine performance, increased fuel consumption, misfires, or the Check Engine Light turning on.

3. What causes the P12C0 code to appear?

Possible causes include a faulty fuel injector, a malfunctioning injection timing control solenoid, wiring or connector issues, or problems with the ECM.

4. Can I drive with the P12C0 code active?

Itâ€™s not advisable to drive for extended periods with this code active, as it can lead to further engine damage or decreased fuel efficiency.

5. How is the P12C0 code diagnosed?

A technician will use an OBDII scanner to retrieve the code, inspect the fuel injector and related components for damage, and test the injection timing system for proper function.

6. What repairs can fix the P12C0 code?

Repairs may include replacing the faulty fuel injector, repairing damaged wiring or connectors, cleaning carbon deposits, or updating/reprogramming the ECM.

7. Can a dirty fuel injector cause the P12C0 code?

Yes, a dirty or clogged fuel injector can disrupt proper injection timing and trigger this code.

8. How much does it cost to fix the P12C0 code?

Repair costs vary depending on the cause but can range from $150 to $600, including diagnostics, parts, and labor.

9. Can a weak fuel pump cause the P12C0 code?

While less common, a weak fuel pump can contribute indirectly by affecting fuel pressure, which may impact injection timing.

10. How can I prevent the P12C0 code from recurring?

Regular maintenance, such as fuel system cleaning, timely replacement of injectors, and ensuring proper electrical connections, can help prevent this code.