Global SCR Fault Code
Free · no signupSPN 4363 FMI 0 / 16
Black smoke; Poor engine performance; High exhaust backpressure.
System
Not specified
Symptom
Black smoke; Poor engine performance; High exhaust backpressure.
Diagnosis & fix steps
SCR Inlet Temperature High.
LOGIC: Exhaust gas entering the SCR is too hot, risking permanent damage to the catalyst coating.
ACTION: 1. Check for a sticking EGR valve.
2. Check for "hydrocarbon slip" (unburned fuel) from a bad injector or leaking turbo.
FIX: Repair the engine-side fault (EGR, Injector, or Turbo) that is causing high EGT.
Red Seal field insights
If your SCR is overheating, the problem is almost always "upstream" in the engine. If a turbo seal leaks oil into the exhaust, the SCR will "burn" that oil and melt the ceramic brick.
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.
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.
Track this across your whole fleet
This code is free to read. AM Fleet Integrity lets your team log fault codes against assets, plus the full fault-code library, QR operator reporting, PM scheduling and predictive alerts. Start free — no credit card required.
Start your free trialRelated Global SCR fault codes
- SPN 4364 FMI 18Progressive power loss; "Emissions Failure" warning; Excessive DEF consumption.
- SPN 4334 FMI 3 / 4Engine derate; DEF system failure; Possible white smoke from exhaust.
- SPN 5246 FMI 15Dash says "Derate in 30 Minutes"; Alarm beeping; Yellow/Amber warnings.
- SPN 3364 FMI 2 / 17Engine derate; "DEF Symbol" flashing; Machine may eventually lock into 5 MPH or Idle-only.
- SPN 5394 FMI 5"DEF System Error"; No dosing heard; DEF level stays static for days.
- SPN 3361 FMI 31Sudden shutdown or 5 MPH limit; No other active codes; Very difficult to clear.
- SPN 3216 FMI 13 / 20Intermittent Check Engine Light; Sudden derate; Inconsistent emissions data.
- SPN 3031 FMI 2 / 9DEF pump won't engage; Code appears during cold weather; High fuel use.
- SPN 1761 FMI 1 / 18Empty tank warning when full; Machine shutdown; Alarm buzzer.