Hyundai C1102
Inspect 12V charging system & battery C1603 – Thermal protection. Wait 20-30 seconds for the system to cool down. 2015-2017MY SONATA (LFA, LF HEV/PHEV) MDPS (WARRANTY EXTENSION TXX
Quick answer
For verified 2016–2017 US Hyundai Sonata applicability, C1102 directs inspection of the 12V charging system and battery. The supplied Hyundai MDPS bulletin also lists C1603 as thermal protection and says to wait 20–30 seconds for the system to cool down.
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1. What does C1102 mean?
For verified 2016–2017 US Hyundai Sonata applicability, C1102 directs inspection of the 12V charging system and battery. The supplied Hyundai MDPS bulletin also lists C1603 as thermal protection and says to wait 20–30 seconds for the system to cool down.
2. Technical explanation
Hyundai TSBs 22-ST-001H and 23-ST-003H identify C1102 as: “Inspect 12V charging system & battery.” In the same diagnostic material, C1603 is identified as “Thermal protection,” with the instruction to wait 20–30 seconds for the system to cool down. The bulletins also direct checks of DTCs and wiring at the HECU, R-MDPS, and EMS, including connector connection quality, corrosion, and damage or deformation. If DTCs remain present, the cited procedure states to replace the short-gear assembly.
3. What system is affected?
The verified bulletin context is Hyundai MDPS, with diagnostic checks involving the HECU, R-MDPS, EMS, 12V charging system, and 12V battery.
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
Not yet established by verified evidence.
6. Possible causes
- The verified C1102 instruction is to inspect the 12V charging system and battery.
- The bulletins direct inspection for poor connector connection, connector corrosion, and connector damage or deformation at the HECU, R-MDPS, and EMS.
- C1603 is identified in the same bulletin material as thermal protection.
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 C1603 is present, wait 20–30 seconds for the system to cool down, as stated in the Hyundai bulletin.
- Have diagnosis performed using the Hyundai MDPS diagnostic procedure and DTC diagnostic guide referenced by the bulletin.
10. Step-by-step troubleshooting
- Inspect the 12V charging system and battery for C1102.
- Check DTCs and wiring at the HECU, R-MDPS, and EMS.
- Check connectors for poor connection.
- Check connectors for corrosion.
- Check connectors for damage or deformation.
- Re-check DTCs after the applicable diagnostic steps.
11. When to contact service
Contact an authorized Hyundai service provider for MDPS diagnostic inspection, especially if the DTC remains present after the specified checks.
12. What the service center may check
- Retrieve and re-check DTCs using the vehicle OBD2 diagnostic connection.
- Inspect the 12V charging system and battery for C1102.
- Inspect HECU, R-MDPS, and EMS wiring and connectors for poor connection, corrosion, damage, or deformation.
- Use the Hyundai DTC Diagnostic Guide referenced by the bulletin.
13. Possible repair or resolution
- If DTCs are still present after the bulletin-directed checks, the cited procedure recommends replacement of the short-gear assembly.
14. Affected vehicles
- Hyundai Sonata · 2016–2017 · US
15. Related TSBs / service bulletins
- Hyundai TSB 22-ST-001H, published January 6, 2022: MDPS diagnostic inspection for 2015–2017 Sonata (LFA, LF HEV/PHEV) under Warranty Extension TXXO. It lists C1102 as inspection of the 12V charging system and battery, and C1603 as thermal protection with a 20–30 second cooldown instruction.
- Hyundai TSB 23-ST-003H, published April 10, 2023: MDPS diagnostic inspection for 2015–2017 Sonata and Sonata Hybrid/Plug-In under Warranty Extension TXXO. It contains the same cited C1102 and C1603 guidance.
16. Recall information
No recall relationship is established by verified evidence.
17. Official manufacturer information
Official NHTSA-hosted Hyundai manufacturer communications: TSB 22-ST-001H (https://static.nhtsa.gov/odi/tsbs/2022/MC-10207815-0001.pdf) and TSB 23-ST-003H (https://static.nhtsa.gov/odi/tsbs/2023/MC-10235349-0001.pdf). Verified applicability supplied for this record is 2016–2017 Hyundai Sonata, US.
19. Frequently asked questions
What does Hyundai C1102 mean in the supplied bulletin evidence?
It directs inspection of the 12V charging system and battery.
What does C1603 mean in the supplied Hyundai bulletin evidence?
It is identified as thermal protection. The bulletin says to wait 20–30 seconds for the system to cool down.
What wiring and connector areas does the bulletin specify?
The bulletin specifies checking DTCs and wiring at the HECU, R-MDPS, and EMS, and inspecting connectors for poor connection, corrosion, damage, or deformation.
What does the cited procedure recommend if DTCs remain present?
It recommends replacement of the short-gear assembly.
Is this verified as a safety recall?
Not yet established by verified evidence.