P24EE
- Powertrain
- Manufacturer-specific
- Emissions
Diagnose soon
Usually safe to drive short distances, but the fault will not clear itself and can worsen or fail an emissions test.
NH3 Sensor Processor Performance
This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.
The microcontroller inside the smart NH3 slip sensor reports an internal performance fault — failed self-test, watchdog reset, or out-of-range plausibility checks. The sensor cannot guarantee its output value, the ECM marks the channel invalid and disables SCR closed-loop control on this branch.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Usually safe to drive short distances, but the fault will not clear itself and can worsen or fail an emissions test.
- Urgency
- Diagnose soon
- Will it pass emissions
- No
- Check engine light
- Solid
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Internal processor or firmware fault | Very common | — |
| 2 | Brown-out from supply voltage dips | Common | — |
| 3 | Module software outdated, reflash may resolve | Occasional | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
- Nh3 Sensor
- Sensor Microcontroller
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Awaiting review
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