Powertrain, generic (extended)

P24FE SCR Catalyst Incorrect

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P24FE means the controller concludes that the SCR catalyst is missing or not the expected part. Ford runs this test on the 6.7 L diesel (2023 summary) for about 60 s with SCR inlet at 195–340 °C and feedgas NOx of 70–500 ppm, and sets the code when cumulative SCR efficiency falls below 0 %. Hino's J08E workshop text (SB-19-008, 2017–2020 conventional trucks) treats it as removal of the DEF SCR catalyst: average NOx conversion at or under 0.03 for 10 s, MIL off but service lamp on, low power. Hino alert SA-17-036 had first told dealers to clear and release trucks. Ford TSB 24-2136 links P24FE on 2020–2022 Super Duty to NOx sensor 11, fixed by a new sensor and software. Ordinary ageing is P20EE.

Likely causes

Upstream or downstream NOx sensor misreading (Ford sensor 11, Hino NOx sensors)
SCR catalyst removed or replaced by a non-matching part
Controller software detecting removal falsely, fixed by reprogramming
Diluted DEF or faulty DEF injector collapsing NOx conversion

Symptoms

  • Warning or service lamp (Hino sets the service lamp, MIL stays off)
  • Reduced engine power
  • NOx downstream of the SCR as high as upstream in live data

Repair estimate

DifficultyHardWorkshop job
Parts and labour€300–4,000
Time0.5–5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

scr catalystnox sensor

Related codes

P20EEP24FDP2201P2209P220E

References: fordservicecontent.com, static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.