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P03512021 Model Year TelemetryCritical Severity

P0351 on 2021 RAM 2500

Ignition Coil A Primary/Secondary Circuit Malfunction

Technical troubleshooting wire for fault code P0351 specifically tailored for the 2021 RAM 2500. Includes wiring sensor pinouts, freeze frame PID parameters, and step-by-step diagnostic tree.

2021 Engine Control Module (ECM) Specific Calibration
RAM 25002021 2500
2021 RAM 2500
Truck6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP)
2021 Stats
Vehicle
2021 2500
6.7L Cummins Turbo-Diesel I6 (420HP / 1,075 lb-ft) / 6.4L HEMI V8 (410HP)
ECU Subsystem
Automotive OBD-II
SAE Mode $01 & $02
Est. Repair Cost
$100 - $350 (DIY: $30 - $90)
OEM Parts & DIY
Urgency Level
Critical
Tow to Shop
Switch 2500 Model Year for P0351

Common 2021 2500 Symptoms

  • Flashing Check Engine Light
  • Severe engine shuddering and jerking under acceleration
  • Hard misfire on Cylinder 1 (accompanied by P0301)
  • Strong smell of unburned gasoline from exhaust

Likely Root Causes on 2021 2500

  • Failed ignition coil pack on Cylinder 1 (Coil A)
  • Broken or melted wiring harness to ignition coil 1
  • Corroded or broken terminal pins in coil electrical connector
  • Burned ignition driver transistor (IGBT) inside the ECM/PCM

Step-by-Step Fix Protocol for 2021 RAM 2500

Step 1: Scan & Record Freeze Frame Data

Connect an OBD-II scanner to the DLC port under the driver dashboard. Record engine RPM, Short Term / Long Term Fuel Trim (STFT/LTFT), and engine coolant temperature at the moment P0351 set.

Step 2: Inspect Wiring Harness & Pin Voltages

Inspect the sensor connector on the 2021 2500 engine bay. Use a multimeter to verify reference voltage (5.0V / 12.0V) and ground continuity.

Step 3: Component Replacement & PCM Reset

Replace the verified defective component using OEM or equivalent grade parts. Clear DTC P0351 and complete an EPA drive cycle to verify readiness monitors set to READY.

Recommended Parts & Testing Tools

Equipment for Diagnosing 2021 RAM 2500 (P0351)

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OEM Ignition Component

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

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Pre-gapped iridium spark plugs engineered to restore smooth combustion on 2021 RAM 2500.

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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.

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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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