Chevrolet U3620
U362E and U3630-U3636, with symptom 17 or 9 ALREADY set, go to SI and follow the published SI diagnostic/repair procedures. After above re
Quick answer
For applicable Chevrolet Bolt EV and Bolt EUV vehicles, verified GM/NHTSA communications state that if U3620 is present with symptom 17 or 9 already set, technicians should use Chevrolet Service Information (SI) and follow the published diagnostic/repair procedures. A false DTC condition is also described in a 2024 communication.
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 U3620 mean?
For applicable Chevrolet Bolt EV and Bolt EUV vehicles, verified GM/NHTSA communications state that if U3620 is present with symptom 17 or 9 already set, technicians should use Chevrolet Service Information (SI) and follow the published diagnostic/repair procedures. A false DTC condition is also described in a 2024 communication.
2. Technical explanation
U3620 is documented in official manufacturer communications alongside U362E and U3630–U3636. The supplied evidence does not provide a standalone component-level definition for U3620. The September 2024 communication states that certain listed vehicles may set a false DTC. It directs that when U3620–U362E or U3630–U3636 has symptom 17 or 9 already set, SI diagnostic/repair procedures must be followed; after those repairs, the field action instructions apply.
3. What system is affected?
Not yet established by verified evidence. One official communication excerpt references a propulsion-related message and charging limited to 30% state of charge, but the supplied evidence does not establish a specific failed system or component for U3620.
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
- A propulsion-related DIC message is referenced in one official communication excerpt.
- Charging may be limited to 30% state of charge in the condition described by one official communication excerpt.
- Symptom status 17 or 9 is specifically referenced in the applicable service direction.
6. Possible causes
- Certain vehicles may have a condition in which a false DTC is set.
- Any additional root cause for U3620 is not yet established by verified evidence.
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. One official communication excerpt references charging limited to 30% state of charge.
9. What you can safely do
- Have the vehicle evaluated using Chevrolet published Service Information diagnostic/repair procedures when U3620 is present with symptom 17 or 9 already set.
- Use an authorized Chevrolet service provider for diagnosis and repairs.
10. Step-by-step troubleshooting
- Confirm whether U3620 is present and whether symptom 17 or 9 is already set.
- For U3620–U362E or U3630–U3636 with symptom 17 or 9 already set, follow the published Chevrolet SI diagnostic/repair procedures.
- After the SI-directed repairs, follow the applicable field-action instructions. The supplied excerpts do not provide the complete procedure.
11. When to contact service
Contact an authorized Chevrolet dealer or qualified Chevrolet EV service provider. Provide DTC U3620, the vehicle identification number, and any propulsion message or charging limitation observed.
12. What the service center may check
- Retrieve and document DTC U3620 and associated symptom status.
- Follow Chevrolet SI diagnostic/repair procedures when symptom 17 or 9 is already set.
- Determine whether the applicable Chevrolet field action applies after SI-directed repairs.
- Evaluate whether the reported DTC is a false DTC condition described by the September 2024 manufacturer communication.
13. Possible repair or resolution
- The verified communications direct SI-based diagnosis and repair before applying the field-action instructions.
- A specific repair, part replacement, software update, or final resolution is not established by the supplied evidence.
14. Affected vehicles
- Chevrolet Bolt EUV · 2020–2022 · US
- Chevrolet Bolt EUV · 2020–2023 · US
- Chevrolet Bolt EV · 2020–2022 · US
- Chevrolet Bolt EV · 2020–2023 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication 10252566, N242437530, published April 3, 2024: references U3620–U362E and U3630–U3636 with symptom 17 and directs use of SI diagnostic/repair procedures.
- NHTSA Manufacturer Communication 10252968, N242437530-01, published April 8, 2024: references U3620–U362E and U3630–U3636 with symptom 17 already set and directs use of SI diagnostic/repair procedures.
- NHTSA Manufacturer Communication 11008165, N242443490, published September 26, 2024: states certain listed vehicles may set a false DTC and directs SI diagnostic/repair procedures when U3620–U362E or U3630–U3636 has symptom 17 or 9 already set.
16. Recall information
- No recall is established by the supplied verified evidence.
17. Official manufacturer information
Verified source: NHTSA Manufacturer Communication PDF 11008165, N242443490, published September 26, 2024: https://static.nhtsa.gov/odi/tsbs/2024/MC-11008165-0001.pdf
19. Frequently asked questions
What should be done if U3620 has symptom 17 or 9 set?
The verified September 2024 manufacturer communication directs technicians to Chevrolet SI and to follow the published SI diagnostic/repair procedures.
Can U3620 be a false code?
The verified September 2024 communication states that certain listed vehicles may have a condition where a false DTC is set. It does not establish that every U3620 is false.
Which vehicles are covered by the supplied applicability data?
Chevrolet Bolt EV and Bolt EUV vehicles for model years 2020–2023 in the US are listed, with overlapping entries also listing 2020–2022.