AutoFixDB - Free OBD-II diagnostic trouble code lookup. Find causes, symptoms, diagnostic steps and repair solutions.

Overview

OBD-II P01A2 code indicates an intermittent/erratic signal in the alternative fuel tank A pressure sensor circuit, often relating to sensor wiring, connector issues, or sensor failure; classification may vary by vehicle and some references list code as reserved with no official definition.

Common Symptoms

Check Engine Light (MIL) illuminated
Stored intermittent/erratic fault in fuel tank pressure monitoring
Possible EVAP or fuel system warning depending on make

Most Common Causes

Faulty alternative fuel tank A pressure sensor medium

Sensor may intermittently send erratic signals triggering the code

Wiring harness or connector issue at pressure sensor medium

Corrosion, loose connectors, or broken wires can cause intermittent circuit faults

ECU/PCM fault in interpreting sensor circuit low

Less common; requires specific vehicle diagnostic data

Alternative fuel tank issue (e.g., leak, damage) low

Some references suggest tank integrity issues may contribute

Diagnostic Steps

Retrieve code with appropriate OBD-II scanner supporting extended codes

Expected: P01A2 stored or pending

Interpretation: Confirms fault present in pressure sensor circuit
Visually inspect wiring and connectors to the alternative fuel tank A pressure sensor

Expected: No visible corrosion, breaks, or loose connections

Interpretation: If issues found, repair and clear code
Test the alternative fuel tank A pressure sensor signal with a multimeter/diagnostic tool

Expected: Stable signal within manufacturer specs

Interpretation: Erratic readings indicate sensor fault
If available, consult OEM service manual for specific sensor circuit tests

Expected: Reference values for sensor voltage/current

Interpretation: Deviation from expected values confirms sensor or ECU issue

Repair Solutions

Repair or replace wiring/connectors to pressure sensor medium

Estimated Cost: $50 - $200

Repair costs depend on labor and extent of wiring damage

Replace alternative fuel tank A pressure sensor medium

Estimated Cost: $100 - $400

Cost varies by vehicle make/model and sensor part price

ECU/PCM diagnostic and repair if internal fault hard

Estimated Cost: $300 - $1000

Only if confirmed after sensor and wiring checks

Common Misdiagnoses

Avoid these common diagnostic mistakes:

Assuming a general fuel system performance issue unrelated to the specific pressure sensor circuit
Confusing with reserved/unassigned code lists

Frequently Asked Questions

What is the definition of the P01A2 engine code?

The P01A2 code stands for Alternative Fuel Tank A Pressure Sensor Circuit Intermittent/Erratic. This generally indicates an issue with the Fuel System system.

Can P01A2 cause engine damage?

With a severity level of medium, may cause check engine light illumination; potential impact on fuel system monitoring; limited direct drivability issues

What happens when the P01A2 code is active?

Common symptoms include: Check Engine Light (MIL) illuminated, Stored intermittent/erratic fault in fuel tank pressure monitoring, Possible EVAP or fuel system warning depending on make. You might also notice the Check Engine Light is on.

Potential causes for OBDII code P01A2

It can be caused by several factors, most notably: Faulty alternative fuel tank A pressure sensor, Wiring harness or connector issue at pressure sensor, ECU/PCM fault in interpreting sensor circuit.

What is the price difference for fixing P01A2?

The cost varies significantly based on the root cause. For example, replacing a Repair or replace wiring/connectors to pressure sensor typically costs between $50 and $200, while fixing a ECU/PCM diagnostic and repair if internal fault can range from $300 to $1000.

Is P01A2 a generic or manufacturer-specific code?

This is a universal code. You might see P01A2 on Ford, Chevrolet, Toyota, Honda, Nissan, or any other OBD-II vehicle.

P01A2: Alternative Fuel Tank A Pressure Sensor Circuit Intermittent/Erratic