Diagnostic article Generic OBD-II
P2026: low EVAP temperature-circuit voltage is not a cold-vapor diagnosis
Audi's CAED P2026 monitor uses a 0–3.25 V signal region, so the low-voltage label should be kept separate from actual fuel-vapor temperature.
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Documented application
Audi 2014 A6/S6 Quick Reference Specification Book, September 2013, Engine Code CAED, DTC chart. Thresholds only describe this documented monitor; not universal across other makes or engines.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
P2026 is the low-voltage fault for the EVAP fuel-vapor temperature-sensor circuit. Audi's CAED chart lists a signal region from 0 to 3.25 V as the malfunction criterion. The number belongs to the electrical signal, not to a temperature scale.
Low voltage does not establish low temperature
The row does not publish a transfer function converting voltage to fuel-vapor temperature. As diagnostic interpretation, the circuit-low label cannot be used on its own to claim that vapor in the tank is unusually cold. The signal may be unreliable because the circuit is in the reported fault condition.
Likewise, this is not a tank-pressure or EVAP leakage threshold. A pressure test result and this electrical criterion answer different questions.
Use the signal region in the proper context
The published values are in a malfunction table and should not be represented as the sensor's normal operating range. Audi supplies no connector pin, universal resistance value or required replacement in this row. Use the CAED circuit procedure to establish the test state and explain the low feedback. This scoped description comes from the 2014 A6/S6 reference book and does not automatically apply to another engine's EVAP temperature implementation.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
EVAP Fuel Vapor Temperature Sensor Circuit Low Voltage
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT