Toyota U1110
2021 model year Highlander, Highlander Hybrid, RAV4, and RAV4 Hybrid; and 2021 model year RAV4 Prime vehicles equipped with Premium Audio (version 1383) may experie
Quick answer
Toyota DTC U1110 is listed by Toyota in T-SB-0019-21 Rev. as an intermittent DTC that may occur on certain Premium Audio-equipped vehicles addressed by an Audio Head Unit Software Update (Denso-Ten).
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 U1110 mean?
Toyota DTC U1110 is listed by Toyota in T-SB-0019-21 Rev. as an intermittent DTC that may occur on certain Premium Audio-equipped vehicles addressed by an Audio Head Unit Software Update (Denso-Ten).
2. Technical explanation
Verified evidence does not establish a standalone diagnostic definition for U1110. The supplied Toyota/NHTSA bulletin evidence identifies it only as one of several intermittent DTCs associated with the bulletin’s multimedia/audio head-unit software concern.
3. What system is affected?
The verified bulletin title identifies the affected area as the Audio Head Unit Software Update (Denso-Ten).
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
- Toyota’s bulletin lists U1110 as an intermittent DTC.
- The bulletin evidence also lists abnormal charging-icon operation on the charging screen.
- Audio information may not be displayed on the meter’s Audio tab.
- The HVAC AUTO control may have a delay when turned off from the multimedia screen.
- HVAC settings may display differently since the last ACC-OFF.
- HVAC blower-motor operation may not display while in AUTO.
- Bluetooth may not reconnect after an Android Auto phone call.
- Bluetooth audio may play after connecting and disconnecting Android Auto.
6. Possible causes
- Toyota’s supplied bulletin evidence associates the condition with an Audio Head Unit Software Update (Denso-Ten).
- A more specific root cause for U1110 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.
9. What you can safely do
- Record whether U1110 is intermittent and note any associated multimedia, meter-display, HVAC-display, Bluetooth, or charging-screen behavior.
- Provide the Toyota dealer with the DTC and the applicable Toyota bulletin reference before authorizing diagnosis or repair.
10. Step-by-step troubleshooting
- Check whether the vehicle matches a verified applicable Toyota model year and US-market application.
- Have a Toyota dealer evaluate whether T-SB-0019-21 Rev. applies and whether the specified Audio Head Unit Software Update is appropriate.
- Do not infer a high-voltage charging-system fault from U1110 based on the supplied evidence alone.
11. When to contact service
Contact a Toyota dealer or qualified Toyota service provider for confirmation of applicability and bulletin-based diagnosis. Service urgency is not established by verified evidence.
12. What the service center may check
- Confirm the vehicle model year, model, market, and Premium Audio configuration.
- Retrieve and document all stored and history DTCs, including the other intermittent DTCs named in the bulletin.
- Verify the installed audio head-unit software version and bulletin eligibility using Toyota service information.
13. Possible repair or resolution
- Toyota’s verified bulletin evidence identifies an Audio Head Unit Software Update (Denso-Ten) as the bulletin subject.
- The supplied evidence does not establish a guaranteed repair outcome for U1110.
14. Affected vehicles
- Toyota Prius Prime · 2021–2022 · US
- Toyota Prius Prime · 2021 · US
- Toyota RAV4 Prime · 2021–2022 · US
- Toyota RAV4 Prime · 2021 · US
15. Related TSBs / service bulletins
- Toyota T-SB-0019-21 Rev., Audio Head Unit Software Update (Denso-Ten), published through NHTSA manufacturer communications including MC-10201369 and MC-10204562.
- The supplied evidence states that some 2020–2021 Highlander, Highlander Hybrid, RAV4, and RAV4 Hybrid vehicles, and some 2021 RAV4 Prime vehicles equipped with Premium Audio version 1383, may experience the listed concerns. Applicability data also identifies US-market 2021–2022 Prius Prime and RAV4 Prime entries; the supplied excerpt does not establish the complete bulletin conditions for those entries.
16. Recall information
- No recall is established by the supplied verified evidence.
17. Official manufacturer information
Official NHTSA-hosted Toyota manufacturer communications: https://static.nhtsa.gov/odi/tsbs/2021/MC-10204562-9999.pdf and https://static.nhtsa.gov/odi/tsbs/2021/MC-10201369-9999.pdf
19. Frequently asked questions
What does Toyota U1110 mean?
The supplied verified evidence does not provide a standalone definition. It identifies U1110 as an intermittent DTC in Toyota’s Audio Head Unit Software Update bulletin.
Is U1110 a charging-system fault?
Not established by verified evidence. The bulletin mentions abnormal charging-icon operation on the charging screen, but it does not establish that U1110 indicates a charging-system fault.
Which vehicles are identified in the supplied applicability data?
US-market Toyota Prius Prime for 2021 and 2021–2022, and US-market Toyota RAV4 Prime for 2021 and 2021–2022. The supplied bulletin excerpt separately names certain 2021 RAV4 Prime vehicles with Premium Audio version 1383.
Is there a recall for U1110?
No recall is established by the supplied verified evidence.