Land Rover P0A78
49 in the Electric Power Inverter Converter. • Additional details are available in SSM76229 on TOPIx. For both the above concerns, new sof
Quick answer
For certain U.S. 2023 and 2025 Land Rover Range Rover vehicles, DTC P0A78-49 may be stored in the Electric Power Inverter Converter (EPIC). Land Rover manufacturer communications state that new EPIC software has been released through TOPIx for this concern.
This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.
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1. What does P0A78 mean?
For certain U.S. 2023 and 2025 Land Rover Range Rover vehicles, DTC P0A78-49 may be stored in the Electric Power Inverter Converter (EPIC). Land Rover manufacturer communications state that new EPIC software has been released through TOPIx for this concern.
2. Technical explanation
The supplied verified evidence identifies P0A78-49 as a DTC stored in the Electric Power Inverter Converter (EPIC). A Land Rover manufacturer communication also states that P0A1B, described there as “Drive Motor ‘A’ Control Module Performance,” may be present. The supplied diagnostic title and meaning are truncated source text; they do not establish a complete generic definition of P0A78.
3. What system is affected?
Electric Power Inverter Converter (EPIC).
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
- DTC P0A78-49 stored in the EPIC.
- A “Stop Safely Electrical Fault Detected” instrument-panel warning message is referenced in Land Rover manufacturer communications.
- P0A1B may also be stored, according to a Land Rover manufacturer communication.
6. Possible causes
- The verified evidence identifies a software update for the EPIC concern. It does not establish a component-level root cause.
7. Can I still drive the vehicle?
Not yet established by verified evidence.
8. Can I charge the vehicle?
Not yet established by verified evidence.
9. What you can safely do
- If a “Stop Safely Electrical Fault Detected” warning is displayed, arrange assessment by an authorized Land Rover retailer or qualified service facility.
- Have the vehicle checked for stored EPIC DTCs and applicable TOPIx software updates.
- Do not attempt high-voltage inverter or converter repairs yourself.
10. Step-by-step troubleshooting
- Use approved diagnostic equipment to confirm whether P0A78-49 is stored in the EPIC.
- Check whether P0A1B is also stored, as referenced by the manufacturer communication.
- Consult the applicable Land Rover TOPIx service information, including SSM76229 as referenced in the supplied evidence.
- Confirm whether the applicable new EPIC software is available through TOPIx.
11. When to contact service
Contact an authorized Land Rover retailer or qualified service facility for diagnosis and confirmation of applicable EPIC software updates.
12. What the service center may check
- Confirm DTC P0A78-49 in the Electric Power Inverter Converter.
- Check for P0A1B – Drive Motor “A” Control Module Performance, which may also be present.
- Review TOPIx information referenced by Land Rover, including SSM76229.
- Determine whether the new EPIC software referenced in the manufacturer communications applies to the vehicle.
13. Possible repair or resolution
- Land Rover manufacturer communications state that new EPIC software has been released on TOPIx for DTC P0A78-49 in the EPIC.
- The supplied evidence does not establish any additional repair or parts replacement.
14. Affected vehicles
- Land Rover Range Rover · 2023 · US
- Land Rover Range Rover · 2025 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication 11020304, SSM76347, published June 25, 2025: references DTC P0A78-49 stored in the EPIC.
- NHTSA Manufacturer Communication 11018308, TUCC_MAY2025_31, published May 9, 2025: references P0A78-49 in the EPIC, possible P0A1B, and a “Stop Safely Electrical Fault Detected” warning.
- NHTSA Manufacturer Communication 11013930, MRC_JAN2025_51, published January 17, 2025: states that new EPIC software has been released through TOPIx and references SSM76229.
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Verified NHTSA-hosted Land Rover manufacturer communications: https://static.nhtsa.gov/odi/tsbs/2025/MC-11020304-0001.pdf ; https://static.nhtsa.gov/odi/tsbs/2025/MC-11018308-0001.pdf ; https://static.nhtsa.gov/odi/tsbs/2025/MC-11013930-0001.pdf
19. Frequently asked questions
What does P0A78-49 indicate on the covered Land Rover Range Rover?
The verified evidence states that P0A78-49 is stored in the Electric Power Inverter Converter (EPIC). A complete generic code definition is not established by the supplied evidence.
Which vehicles are established as applicable?
The supplied applicability data identifies U.S. 2023 and 2025 Land Rover Range Rover vehicles.
Is there a Land Rover service action?
Yes. Land Rover manufacturer communications state that new EPIC software has been released through TOPIx for this concern. Applicability to an individual vehicle must be confirmed by the servicing retailer.
Can P0A1B occur with P0A78-49?
Yes. One supplied Land Rover manufacturer communication states that P0A1B – Drive Motor “A” Control Module Performance – might also be stored.
Is P0A78-49 associated with a recall?
Not yet established by verified evidence.