AutoCodes – Generic – P3156

P3156 Code - Cylinder 3 High-Pressure Fuel Injector High Side Circuit High

Quick Answer

The solenoid-controlled injection valve discharges a high-pressure spray into the combustion chamber. Common causes include Faulty Fuel Injector 3, Fuel Injector 3 harness is open or shorted, Fuel Injector 3 circuit poor electrical connection. 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: P3156 indicates Cylinder 3 High-Pressure Fuel Injector High Side Circuit High.
Common causes: Common causes include Faulty Fuel Injector 3, Fuel Injector 3 harness is open or shorted, Fuel Injector 3 circuit poor electrical connection.
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 1,016

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 Jul 16, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P3156 Description

The solenoid-controlled injection valve discharges a high-pressure spray into the combustion chamber. The solenoid-controlled injection valve is a retracting-plunger valve characterized by a high level of flexibility in its spray-propagation pattern (angle and shape). The discharge orifices form the high-precision injection pattern. This provides even and consistent propagation. The retracting-plunger solenoid-controlled injection valve continues to maintain stable propagation properties, even at the temperatures and pressure levels encountered within the combustion chamber. Fuel is injected into the combustion chambers under high pressure (between 50 and 200 bar) during the intake and compression strokes. During the warm-up phase yet another, a minute quantity of fuel is injected to assist the catalytic converter to reach its effective operating temperature more quickly (catalytic converter heating). During cold starting, the fuel is sprayed during the compression stroke in multiple pulses. This strategy provides reliable cold-starts along with substantive improvements in the areas of pollutant emissions and fuel consumption.
The Digital Motor Electronics (DME) diagnosis monitors the activation of the high voltage side of the fuel injector. The Diagnostic Trouble Code (DTC) is detected when there is a short circuit to B+.

OBDII Code P3156 - Cylinder 3 High-Pressure Fuel Injector High Side Circuit High - AutoCodes.com — P3156 Code - Cylinder 3 High-Pressure Fuel Injector High Side Circuit High

What does this mean?

What are the Possible Causes of the DTC P3156?

Faulty Fuel Injector 3
Fuel Injector 3 harness is open or shorted
Fuel Injector 3 circuit poor electrical connection
Faulty Digital Motor Electronics (DME)

How to Fix the DTC P3156?

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 P3156 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 P3156 code?

Need more information on how to fix the P3156 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P3156 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P3156 BMW — Cylinder 3 High-Pressure Fuel Injector High Side Circuit High
P3156 MINI — Cylinder 3 High-Pressure Fuel Injector High Side Circuit High

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 P3156 Code

1. What does OBDII code P3156 mean?

Code P3156 indicates that the high-pressure fuel injector circuit for cylinder 3 is showing a high voltage condition, which may indicate an electrical fault or a problem within the injector circuit.

2. What are the symptoms of code P3156?

Common symptoms include poor engine performance, misfires in cylinder 3, reduced fuel efficiency, difficulty starting the engine, and the check engine light being illuminated.

3. What causes the P3156 code?

Possible causes include a faulty fuel injector, damaged wiring or connectors in the injector circuit, a malfunctioning powertrain control module (PCM), or excessive resistance in the circuit.

4. Can I drive with a P3156 code?

While driving with this code is possible, it is not recommended as it can lead to poor performance, further engine damage, or unsafe driving conditions due to misfires or power loss.

5. How do I diagnose code P3156?

Start by inspecting the wiring and connectors for cylinder 3â€™s injector for damage or loose connections. Test the injectorâ€™s resistance and voltage, and verify the PCM is functioning properly.

6. How is code P3156 fixed?

Repairs may involve replacing the high-pressure fuel injector for cylinder 3, repairing damaged wiring or connectors, or reprogramming or replacing the PCM if necessary.

7. What tools are needed to fix a P3156 code?

Basic tools include a multimeter for checking voltage and resistance, a scan tool for clearing codes, and possibly specialized tools for removing and replacing the injector.

8. How much does it cost to repair a P3156 code?

Repair costs vary depending on the issue. Replacing a fuel injector can range from $200 to $500, while wiring repairs or PCM replacement can cost more.

9. Can a dirty fuel injector cause code P3156?

No, this code specifically relates to an electrical fault in the circuit and not injector clogging. However, cleaning a dirty injector will not resolve this issue.

10. Does the P3156 code affect emissions?

Yes, unresolved injector circuit issues can disrupt fuel delivery and combustion, potentially increasing emissions and causing a failed emissions test.