AutoCodes – Cadillac – P1E28 Cadillac

P1E28 Cadillac Code - Auxiliary Transmission Fluid Pump Control Module Hybrid/EV Battery System Voltage

Quick Answer

The power inverter module, often referred to as the drive motor generator power inverter module, contains three motor control modules and the hybrid powertrain control module. Common causes include Program Power Inverter Module, Faulty Power Inverter Module, Power Inverter Module harness is open or shorted. 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: P1E28 Cadillac indicates Auxiliary Transmission Fluid Pump Control Module Hybrid/EV Battery System Voltage.
Common causes: Common causes include Program Power Inverter Module, Faulty Power Inverter Module, Power Inverter Module harness is open or shorted.
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 802

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 Apr 23, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1E28 Cadillac Description

The power inverter module, often referred to as the drive motor generator power inverter module, contains three motor control modules and the hybrid powertrain control module. Two of the motor control modules operate their respective drive motor generator based upon power inverter module commands. The third motor control module controls the auxiliary transmission fluid pump motor. Each drive motor control module monitors its internal high voltage sensor for correct operation, no external circuits are involved. The motor control modules and the hybrid powertrain control module are part of the power inverter module and are not serviced separately.

OBDII Code P1E28 Cadillac - Auxiliary Transmission Fluid Pump Control Module Hybrid/EV Battery System Voltage - AutoCodes.com — P1E28 Cadillac Code - Auxiliary Transmission Fluid Pump Control Module Hybrid/EV Battery System Voltage

What does this mean?

What are the Possible Causes of the DTC P1E28 Cadillac?

Program Power Inverter Module
Faulty Power Inverter Module
Power Inverter Module harness is open or shorted
Power Inverter Module circuit poor electrical connection

How to Fix the DTC P1E28 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 P1E28 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.

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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 P1E28 Cadillac Code

1. What are common symptoms of OBDII code P1E28 in a Cadillac related to the Auxiliary Transmission Fluid Pump Control Module Hybrid/EV Battery System Voltage?

- Common symptoms include poor shifting performance, transmission overheating, and a decrease in fuel efficiency.

2. What are possible causes of OBDII code P1E28 in a Cadillac?

- Possible causes include a faulty auxiliary transmission fluid pump control module, issues with the hybrid/EV battery system voltage, or wiring/connectivity problems.

3. How can I diagnose the OBDII code P1E28 in my Cadillac?

- Diagnosis involves using a scan tool to read the code, checking the auxiliary transmission fluid pump control module, inspecting the hybrid/EV battery system voltage, and examining related wiring for any issues.

4. What should I do if I encounter OBDII code P1E28 in my Cadillac?

- If you encounter this code, it is recommended to have a professional mechanic perform a thorough diagnosis to pinpoint the exact cause of the issue.

5. Can I continue driving my Cadillac with OBDII code P1E28?

- It is not recommended to continue driving your Cadillac with this code present, as it can lead to further damage to the transmission system and potentially affect the vehicle's overall performance.

6. How much does it typically cost to repair OBDII code P1E28 in a Cadillac?

- The cost of repairs for this code can vary depending on the underlying cause, but it may range from a few hundred to over a thousand dollars, including parts and labor.

7. Are there any DIY repair tips for OBDII code P1E28 in a Cadillac?

- DIY repair is not recommended for this particular code, as it involves complex components like the auxiliary transmission fluid pump control module and hybrid/EV battery system that require professional expertise.

8. Can OBDII code P1E28 be caused by a weak hybrid/EV battery in a Cadillac?

- Yes, a weak hybrid/EV battery can contribute to triggering OBDII code P1E28 in a Cadillac, as it may not provide sufficient voltage to power the auxiliary transmission fluid pump control module.

9. Is it safe to reset the OBDII code P1E28 in a Cadillac using a scan tool?

- While resetting the code may temporarily clear the warning light, it is crucial to address the underlying issue causing the code to prevent potential transmission and battery system damage.

10. How often does OBDII code P1E28 occur in Cadillac vehicles?

- This code is relatively rare but can occur in Cadillac vehicles equipped with hybrid or EV technology, particularly if there are issues with the transmission fluid pump control module or battery system voltage.