P24EB
NH3 Sensor Supply Voltage Circuit Low
What it means
The NH3 slip sensor supply voltage drops below the lower limit. Usually a partial short to ground in the supply line, an undersized ground path with high resistance, or an internal supply collapse in the SCR/dosing module. Sensor output is held invalid until the supply recovers.
Is it safe to drive?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Supply line shorted to ground
highOne of the most commonly reported causes for this code — check this first.
High-resistance ground at the SCR module
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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