AutoCodes – Cadillac – P1A9D Cadillac

P1A9D Cadillac Code - Starter/Generator Inverter Phase U 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: P1A9D Cadillac indicates Starter/Generator Inverter Phase U 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 821

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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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 P1A9D Cadillac 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 P1A9D Cadillac - Starter/Generator Inverter Phase U Temperature Sensor Circuit High Voltage - AutoCodes.com — P1A9D Cadillac Code - Starter/Generator Inverter Phase U Temperature Sensor Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P1A9D Cadillac?

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 P1A9D Cadillac?

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 P1A9D Cadillac 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 P1A9D Cadillac code?

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Need Help with the 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 P1A9D Cadillac Code

What does the OBDII code P1A9D mean for my Cadillac?

The OBDII code P1A9D indicates a problem with the Starter/Generator Inverter Phase U Temperature Sensor Circuit, specifically that the voltage is too high.

What are the common symptoms of the P1A9D code?

Common symptoms include warning lights on the dashboard, reduced engine performance, and possible issues with the hybrid system's operation.

What could cause the P1A9D code to trigger?

The code may be triggered by a faulty temperature sensor, damaged wiring or connectors in the circuit, or issues with the inverter itself.

How can I diagnose the P1A9D code?

To diagnose the P1A9D code, use an OBDII scanner to read the code, visually inspect the wiring and connectors for damage, and test the temperature sensor for proper operation.

Can I drive my Cadillac with the P1A9D code?

While you may be able to drive the vehicle, it's not recommended due to the potential for decreased performance and possible damage to the hybrid system. It's best to have it checked by a professional.

What repairs are typically needed for the P1A9D code?

Repairs may include replacing the faulty temperature sensor, repairing damaged wiring, or addressing any issues with the inverter system.

How can I prevent the P1A9D code from recurring?

To prevent recurrence, ensure regular maintenance of the vehicle's electrical system, address any wiring issues promptly, and keep the hybrid system components in good condition.

Is it safe to ignore the P1A9D code?

Ignoring the P1A9D code is not safe, as it can lead to further damage to the hybrid system and affect the vehicle's performance and efficiency.

Will clearing the P1A9D code fix the problem?

Clearing the code will not fix the underlying issue. It's important to diagnose and repair the root cause before clearing the code to prevent it from returning.