P24E4

NH3 Sensor Circuit High

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$56–167 (est.)

Symptoms

Check Engine light comes on
Reduced efficiency of the SCR system
Possible increase in NOx emissions
Reduced engine power in some cases
Errors in the emission control system

Causes

NH3 sensor malfunction
Open or short circuit in the sensor circuit
Problems with connectors or wiring harness
SCR control unit malfunction
Sensor is dirty or damaged

How to Fix

Check the continuity of the electrical circuit of the NH3 sensor
Inspect connectors and wiring harness for damage
Check the functionality of the NH3 sensor
If necessary, replace the NH3 sensor
Check and update the SCR control unit software

Related codes

P24E3 P24E5 P20EE