What are the common causes of P05EB?

A failed SCR inlet temperature sensor. A stuck-open coolant thermostat. A faulty glow plug or block heater. A failing EGR valve. Low DEF quality or dosing.

Read the SCR inlet temperature on a scan tool during a cold start. Check the thermostat for a stuck-open condition. Test the glow plugs or block heater. Check the EGR valve operation. Verify the DEF quality and dosing. Clear the code and retest.

P05EB

Cold Start SCR NOx Catalyst Inlet Temperature Too Low

System: Speed and idle control (P code)
Lamp: Check Engine Light
Category: Powertrain - Computer and Auxiliary Controls

What it means

P05EB means Cold Start SCR NOx Catalyst Inlet Temperature Too Low.

Check these first

A failed SCR inlet temperature sensor
A stuck-open coolant thermostat
A faulty glow plug or block heater
A failing EGR valve
Low DEF quality or dosing

What to do next

Read the SCR inlet temperature on a scan tool during a cold start
Check the thermostat for a stuck-open condition
Test the glow plugs or block heater
Check the EGR valve operation
Verify the DEF quality and dosing
Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.