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P0354 on Mercedes-Benz GLC

Ignition Coil D Primary/Secondary Circuit Malfunction

Factory diagnostic protocol and troubleshooting wire for fault code P0354 specifically for the Mercedes-Benz GLC (2020–2026, 2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC).

Verified OEM Telemetry & Field Repair Tree
Mercedes-Benz GLC2020–2026
Mercedes-Benz GLC
SUV2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
GLC SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$100 - $350 (DIY: $30 - $90)
Parts & Labor DIY
Check P0354 On Another Mercedes-Benz Model:
Diagnose P0354 on Specific GLC Model Year:

1. Symptoms of P0354 on Mercedes-Benz GLC

When the Engine Control Module (ECM/PCM) on your Mercedes-Benz GLC (2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC) logs fault code P0354, drivers commonly observe:

Flashing CEL on Mercedes-Benz GLC (2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC)
Rough running on Mercedes-Benz GLC (2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC)
Loss of power on Mercedes-Benz GLC (2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC)
P0304 code on Mercedes-Benz GLC (2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC)
Mercedes-Benz GLC OBD-II Port Location
The 16-pin diagnostic connector is located Driver lower kick panel near hood release lever. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Mercedes-Benz GLC

Historical warranty claims and technical repair bulletins for Mercedes-Benz GLC point to the following failure distribution:

55%
Dead Cylinder 4 ignition coil (Mercedes-Benz OEM Part)
25%
Wiring damage (Mercedes-Benz OEM Part)
12%
Corroded connector (Mercedes-Benz OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Mercedes-Benz GLC.

3. Step-by-Step DIY Repair Guide for Mercedes-Benz GLC

01
Test Coil with Swap Method

Swap Coil 4 to Cylinder 1. on the Mercedes-Benz GLC equipped with 2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC.

Required Tool: 10mm Socket
02
Replace Coil 4

Install new OEM coil pack. on the Mercedes-Benz GLC equipped with 2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC.

Required Tool: Socket Set
03
Clear DTCs

Clear memory and road test. on the Mercedes-Benz GLC equipped with 2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC.

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Mercedes-Benz GLC (P0354)

Prime Fast Delivery & Verified Fitment
OEM Ignition Component

Direct-Fit Laser Iridium Spark Plugs (Set of 4/6)

4.8 / 5.0 (Top Rated)

Pre-gapped iridium spark plugs engineered to restore smooth combustion on Mercedes-Benz GLC.

$36 – $68 Prime
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Ignition Service Tool

Magnetic Swivel Spark Plug Socket Set

4.8 / 5.0 (Amazon Choice)

360-degree magnetic swivel socket prevents ceramic plug cracks inside deep engine spark wells.

$16.99 Prime
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Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

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Other Common Fault Codes on Mercedes-Benz GLC

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Mercedes-Benz GLC:

4. Mercedes-Benz GLC P0354 FAQs

What causes code P0354 to trigger on a Mercedes-Benz GLC?

On the Mercedes-Benz GLC (2.0L Turbo 4-Cyl with EQ Boost (255HP) / AMG GLC 43 4MATIC), P0354 is most frequently caused by Dead Cylinder 4 ignition coil or Wiring damage.

Where is the OBD-II port located on my Mercedes-Benz GLC?

On the Mercedes-Benz GLC, the 16-pin DLC diagnostic connector is located Driver lower kick panel near hood release lever. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Mercedes-Benz GLC with code P0354?

No. Cylinder 4 ignition coil has failed. Given that P0354 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.