These are code references, not a list of confirmed faults on every vehicle. Read the source and applicability notes, then match the exact vehicle, year, engine and scan report.

When the DEF level sensor cannot provide a trustworthy measurement

reductant level low-circuit code comes from smart-sensor status

Why a DEF level circuit-high label can mean an excessive reported height

Ram DEF-level errors during uneven thawing

Ford calculates insufficient remaining DEF range

Reductant Injection Air Pressure Sensor A Circuit High

Reductant Injection Air Pressure Sensor A Circuit Intermittent

Reductant Temperature Sensor A Circuit

Ford DEF tank temperature fails a cold-start comparison

Reductant Temperature Sensor A Circuit Low

Reductant Temperature Sensor A Circuit High

Reductant Temperature Sensor A Circuit Intermittent

DEF dosing valve 1 open-circuit status

first DEF valve has a low-side short-to-ground indication

first reductant valve control is shorted toward battery supply

reductant pressure feedback below 0.1 V is an electrical finding

The reductant pressure plausibility check before pressurization

Why a zero DEF pressure reading can hide an electrical low signal

high reductant pressure-sensor voltage can display zero pressure

How cumulative pressure movement exposes an erratic DEF signal

reductant pressure did not build after repeated attempts

Reductant Injection Valve Circuit/Open Bank 2 Unit 1

Reductant Injection Valve Circuit Low Bank 2 Unit 1

Reductant Injection Valve Circuit High Bank 2 Unit 1

second DEF metering valve open-circuit evidence

DEF valve 2 low-side ground-short supervision

second DEF valve control has a short-to-supply signature

Reductant Injection Valve Circuit/Open Bank 2 Unit 2

Reductant Injection Valve Circuit Low Bank 2 Unit 2

Reductant Injection Valve Circuit High Bank 2 Unit 2

Reductant Injection Air Pump Control Circuit/Open

high reductant-temperature signal can represent an open circuit

reductant tank temperature disagrees after a cold soak

low tank-temperature signal can represent an electrically hot reading

Why a high DEF temperature-sensor voltage represents a cold extreme

Recognizing an erratic DEF tank temperature signal

Reductant System Performance Bank 2

Reductant Injection Air Pump Control Circuit Low

Reductant Injection Air Pump Control Circuit High

Reductant/Regeneration Supply Control Circuit/Open

Reductant/Regeneration Supply Control Circuit Low

Reductant/Regeneration Supply Control Circuit High

secondary fuel-level inactivity depends on tank state and distance

Fuel level sensor B noise is detected through repeated large changes

A low fuel-level sensor B circuit is not a direct empty-tank measurement

A high fuel-level sensor B circuit should not be read as a full tank

Fuel Level Sensor B Circuit Intermittent

Reductant Quality Sensor Circuit

reductant quality data remains unavailable when it should be ready

quality-sensor circuit low combines measurement and piezo faults

A DEF quality reading above range is not a direct voltage measurement

Intake Manifold Tuning (IMT) Valve Stuck Open Bank 2

Intake Manifold Tuning (IMT) Valve Stuck Closed Bank 2

The tuning-valve open/closed label must be resolved before a jam diagnosis

A tuning-valve jam result needs the source’s endpoint conflict kept visible

Throttle Actuator Control System - Ice Blockage Bank 1

Idle airflow adaptation is compared with a calibration-specific allowance

High-load airflow correlation can fail its learned value or fail to stabilize

Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Bank 1

A tuning-valve performance result can concern SENT data range

The tuning position low-range test uses a bounded raw-voltage window

A high tuning-position code has an impossible printed voltage condition

Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Intermittent Bank 1

Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Bank 2

Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Range/Performance Bank 2

Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Low Bank 2

Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit High Bank 2

Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit Intermittent Bank 2

Ram reductant quality: compare fluid and scan-tool evidence

EGT sensor 1 fails to show the expected post-soak rise

EGT sensor 1 changes faster than the monitor permits

Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 2 Sensor 1

Exhaust Gas Temperature Sensor Circuit Intermittent Bank 2 Sensor 1

EGT sensor 2 has insufficient warming response after soak

rapid raw-temperature changes from EGT sensor 2

Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 2 Sensor 2

Exhaust Gas Temperature Sensor Circuit Intermittent Bank 2 Sensor 2

bank-one intake actuator control is low while its high-side driver is on

cam-actuator high input must be read with driver architecture

Why the DEF pump may stop before an open circuit is identified