Ford P0929:77
2022 Mustang Mach-E, 2022 Escape/Bronco Sport/Maverick/Transit vehicles may exhibit a powertrain malfunction (wrench) indicator with diagnostic trouble code (DTC) P0929:77 stored i
Common search variants: P092977 · P0929-77 · P0929 77 · P0929_77 · Search ignores case and common separators.
Quick answer
Ford service messages identify P0929:77 in the gear shift module (GSM) on certain U.S. 2021–2022 Mustang Mach-E and 2022 Escape vehicles. The documented symptom is a powertrain malfunction/wrench indicator. Ford attributes the condition to GSM software in the cited communications.
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 P0929:77 mean?
Ford service messages identify P0929:77 in the gear shift module (GSM) on certain U.S. 2021–2022 Mustang Mach-E and 2022 Escape vehicles. The documented symptom is a powertrain malfunction/wrench indicator. Ford attributes the condition to GSM software in the cited communications.
2. Technical explanation
P0929:77 is documented by Ford/NHTSA manufacturer communications as being stored in the gear shift module (GSM), rather than being described in the supplied evidence as a battery or charging-system fault. Ford SSM 51057 directs GSM reprogramming with the latest Ford Diagnosis and Repair System (FDRS) software. A later communication, SSM 51191, directs technicians to perform Pinpoint Test D in Workshop Manual section 307-05; if the GSM is not operating correctly, replace the GSM. It specifically states not to perform PMI after installing a new GSM assembly.
3. What system is affected?
Gear Shift Module (GSM).
4. How serious is this code?
Not yet established by verified evidence. The supplied records do not assign a severity level.
5. Symptoms you may notice
- Powertrain malfunction (wrench) indicator.
- DTC P0929:77 stored in the GSM.
6. Possible causes
- Ford SSM 51057 and SSM 51191 state that the condition may be due to software in the GSM.
- If diagnostic testing finds that the GSM is not operating correctly, SSM 51191 directs GSM replacement.
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
- Arrange diagnosis by a Ford dealer or qualified service facility using Ford diagnostic information.
- Provide the technician with DTC P0929:77 and the applicable Ford SSM references.
- Do not attempt GSM programming, module replacement, or high-voltage-related repairs yourself.
10. Step-by-step troubleshooting
- Ford SSM 51191 directs technicians to perform Pinpoint Test D in Workshop Manual section 307-05, Diagnosis and Testing.
- Ford SSM 51057 directs reprogramming the GSM using the latest FDRS software level.
- The supplied evidence does not establish additional owner-level diagnostic steps.
11. When to contact service
Service evaluation is appropriate because Ford provides a specific diagnostic and repair procedure for this condition. The supplied evidence does not establish whether the condition requires immediate towing or whether the vehicle may be driven.
12. What the service center may check
- Confirm P0929:77 is stored in the GSM.
- Perform Pinpoint Test D under Workshop Manual section 307-05, as directed by SSM 51191.
- Apply the latest GSM software using FDRS, as directed by SSM 51057.
- If the GSM is not operating correctly, replace the GSM as directed by SSM 51191.
- Do not perform PMI after installation of a new GSM assembly, per SSM 51191.
13. Possible repair or resolution
- GSM reprogramming with the latest FDRS software is the correction specified in Ford SSM 51057.
- SSM 51191 specifies Pinpoint Test D and GSM replacement if the GSM is found not to be operating correctly.
- The supplied evidence does not establish warranty coverage, repair cost, or an outcome for every vehicle.
14. Affected vehicles
- Ford Escape · 2021–2022 · US
- Ford Mustang Mach-E · 2021–2022 · US
15. Related TSBs / service bulletins
- Ford SSM 51057, published August 31, 2022: covers certain 2021–2022 Mustang Mach-E and 2022 Escape/Bronco Sport/Maverick/Transit vehicles; directs GSM reprogramming with latest FDRS software. NHTSA record: https://static.nhtsa.gov/odi/tsbs/2022/MC-10219068-0001.pdf
- Ford SSM 51191, published November 10, 2022: covers specified build-date ranges and directs Pinpoint Test D; replace the GSM if it is not operating correctly, without PMI after replacement. NHTSA record: https://static.nhtsa.gov/odi/tsbs/2022/MC-10226757-0001.pdf
16. Recall information
- Not yet established by verified evidence. The supplied sources are manufacturer service communications, not recall records.
17. Official manufacturer information
Verified sources: Ford manufacturer communications published through NHTSA: SSM 51057 (https://static.nhtsa.gov/odi/tsbs/2022/MC-10219068-0001.pdf) and SSM 51191 (https://static.nhtsa.gov/odi/tsbs/2022/MC-10226757-0001.pdf). Applicability supplied for this page is U.S. 2021–2022 Escape and U.S. 2021–2022 Mustang Mach-E. The communications also mention other 2022 Ford vehicles, but they are not included in the supplied applicability list.
19. Frequently asked questions
What does P0929:77 indicate in the supplied Ford evidence?
It is documented as stored in the gear shift module (GSM) along with a powertrain malfunction/wrench indicator on specified vehicles.
What repair does Ford specify?
SSM 51057 specifies reprogramming the GSM with the latest FDRS software. SSM 51191 specifies Pinpoint Test D and GSM replacement if the GSM is not operating correctly.
Can I drive or charge the vehicle?
Not yet established by verified evidence.
Is this a recall?
Not yet established by verified evidence. The supplied records are service messages, not recall records.