AutoCodes – Buick – P1AA1 Buick

P1AA1 Buick Code - Starter/Generator Inverter Phase V Temperature Sensor Circuit High Voltage

Quick Answer

The Power Inverter Module (PIM) temperature 1 and 2 sensors are used for overheat protection. Common causes include Faulty Starter/Generator Control Module (SGCM), Starter/Generator Control Module (SGCM) harness is open or shorted, Starter/Generator Control Module (SGCM) circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1AA1 Buick indicates Starter/Generator Inverter Phase V Temperature Sensor Circuit High Voltage.
Common causes: Common causes include Faulty Starter/Generator Control Module (SGCM), Starter/Generator Control Module (SGCM) harness is open or shorted, Starter/Generator Control Module (SGCM) circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 1,247

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Feb 24, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1AA1 Buick Description

The Power Inverter Module (PIM) temperature 1 and 2 sensors are used for overheat protection. The thermistors are located on the control board, near the phase U or V power MOSFET. The Starter/Generator Control Module (SGCM) monitors the inverter temperature sensor for the following:
To detect if the inverter phase U or V temperature sensor is shorted low.
To detect if the inverter phase U or V temperature sensor is shorted high.

OBDII Code P1AA1 Buick - Starter/Generator Inverter Phase V Temperature Sensor Circuit High Voltage - AutoCodes.com — P1AA1 Buick Code - Starter/Generator Inverter Phase V Temperature Sensor Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P1AA1 Buick?

Faulty Starter/Generator Control Module (SGCM)
Starter/Generator Control Module (SGCM) harness is open or shorted
Starter/Generator Control Module (SGCM) circuit poor electrical connection

How to Fix the DTC P1AA1 Buick?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1AA1 Buick code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1AA1 Buick code?

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P1AA1 Buick Code

1. What does the OBDII code P1AA1 mean for a Buick?

The P1AA1 code indicates an issue with the Starter/Generator Inverter Phase V Temperature Sensor Circuit, specifically detecting high voltage.

2. What are the common symptoms of code P1AA1 in a Buick?

Symptoms may include the check engine light turning on, reduced fuel efficiency, limited hybrid system functionality (if equipped), or the vehicle entering limp mode.

3. What causes the P1AA1 code to appear?

Common causes include a faulty Starter/Generator Inverter Phase V Temperature Sensor, damaged or corroded wiring, a loose or poor electrical connection, or a malfunctioning power inverter module.

4. Can I drive my Buick with a P1AA1 code?

While it may be possible to drive the vehicle, it is not recommended as ignoring the issue could lead to further damage to the hybrid or electrical system.

5. How is the P1AA1 code diagnosed?

A technician will use a scan tool to confirm the code, inspect the temperature sensor and its wiring for damage, and test the circuit for high voltage or poor connections.

6. How do I fix a P1AA1 code on my Buick?

Repairs may include replacing the faulty temperature sensor, repairing or replacing damaged wiring, cleaning corroded electrical connections, or recalibrating the inverter system.

7. How much does it cost to repair a P1AA1 code on a Buick?

Repair costs can vary, but replacing a temperature sensor typically costs between $100 and $300, depending on labor and part prices.

8. Can a bad battery cause the P1AA1 code?

A weak or failing battery can cause electrical system issues, but the P1AA1 code is specifically related to the inverter temperature sensor circuit.

9. Will clearing the P1AA1 code with a scan tool fix the issue?

Clearing the code may temporarily turn off the check engine light, but the root cause must be fixed to prevent the code from returning.

10. Is the P1AA1 code unique to Buick vehicles?

While the code is most commonly associated with GM vehicles like Buick, similar issues might occur in related systems on other makes using the same technology.