RAM Fault Code

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P0401

Rough idle; EGR "Service" message; High intake temps.

System

Not specified

Symptom

Rough idle; EGR "Service" message; High intake temps.

Diagnosis & fix steps

EGR Flow Insufficient Detected. LOGIC: The MAP sensor doesn't see a drop in pressure when the EGR valve is commanded open. ACTION: 1. Remove the EGR "Crossover" tube. 2. Check the EGR valve for heavy soot buildup. FIX: Clean EGR valve and Crossover tube; replace EGR valve.

Red Seal field insights

RAM recommends an "EGR Cleaning" service every 67,500 miles. Most owners ignore this until the P0401 pops up. Cleaning the soot out usually restores flow.

Same code keeps coming back?

That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.

Book an uptime review

Read before you touch anything

  • This is general reference information, not a repair manual. It is for trained, qualified technicians.
  • Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
  • Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
  • You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
  • Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.

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