AutoCodes – Mercedes-Benz – P0354 Mercedes-Benz

P0354 Mercedes-Benz Code - Ignition Coil 4 Primary/Secondary Circuit Malfunction

Quick Answer

The ignition system on the vehicle uses individual ignition coils for each cylinder. Common causes include Faulty Ignition Coil 4, Ignition Coil 4 harness is open or shorted, Ignition Coil 4 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: P0354 Mercedes-Benz indicates Ignition Coil 4 Primary/Secondary Circuit Malfunction.
Common causes: Common causes include Faulty Ignition Coil 4, Ignition Coil 4 harness is open or shorted, Ignition Coil 4 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 19,628

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0354 Mercedes-Benz Description

The ignition system on the vehicle uses individual ignition coils for each cylinder. The Engine Control Module (ECM) controls each ignition coil operation. The ECM sends a ON/OFF signal to energize the ignition coil to create a spark at the spark plug when a spark is required at the cylinder.

OBDII Code P0354 Mercedes-Benz - Ignition Coil 4 Primary/Secondary Circuit Malfunction - AutoCodes.com — P0354 Mercedes-Benz Code - Ignition Coil 4 Primary/Secondary Circuit Malfunction

What does this mean?

What are the Possible Causes of the DTC P0354 Mercedes-Benz?

Faulty Ignition Coil 4
Ignition Coil 4 harness is open or shorted
Ignition Coil 4 circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P0354 Mercedes-Benz?

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 P0354 Mercedes-Benz 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 P0354 Mercedes-Benz code?

Need more information on how to fix the P0354 Mercedes-Benz code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0354 Mercedes-Benz code diagnosed by a professional: Find a repair shop in your area

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 P0354 Mercedes-Benz Code

1. What are common symptoms of OBDII code P0354 in a Mercedes-Benz?

- Common symptoms include engine misfires, rough idling, loss of power, and illuminated check engine light.

2. What causes the OBDII code P0354 in a Mercedes-Benz?

- The code P0354 is typically triggered by a faulty ignition coil in the primary or secondary circuit of cylinder 4.

3. How can I diagnose the issue causing OBDII code P0354 in my Mercedes-Benz?

- You can use a scan tool to check for the specific cylinder misfire code, then inspect the ignition coil, spark plugs, and wiring for any signs of damage.

4. Can a bad spark plug cause OBDII code P0354 in a Mercedes-Benz?

- Yes, a faulty spark plug can lead to misfires and trigger the P0354 code if it causes issues in the ignition coil's primary or secondary circuit.

5. What is the recommended repair for OBDII code P0354 in a Mercedes-Benz?

- The recommended repair is to replace the ignition coil for cylinder 4 to address the primary/secondary circuit malfunction.

6. Are there any tips for preventing OBDII code P0354 in a Mercedes-Benz?

- Regular maintenance, such as timely spark plug replacement and inspection of ignition components, can help prevent issues leading to the P0354 code.

7. Can driving with OBDII code P0354 in a Mercedes-Benz cause further damage?

- Continuing to drive with the P0354 code may lead to increased fuel consumption, potential catalytic converter damage, and further engine performance issues.

8. How much does it typically cost to repair OBDII code P0354 in a Mercedes-Benz?

- The cost of repairing the P0354 code can vary depending on the labor rates and parts prices, but it generally ranges from $150 to $300 for the ignition coil replacement.

9. Is it safe to clear the OBDII code P0354 in a Mercedes-Benz without fixing the issue?

- Clearing the code without addressing the underlying problem may temporarily turn off the check engine light, but it will not resolve the root cause of the malfunction.

10. Can a DIY enthusiast replace the ignition coil to fix OBDII code P0354 in a Mercedes-Benz?

- Yes, replacing the ignition coil for cylinder 4 can be a relatively straightforward DIY task for those with some automotive knowledge and the right tools.