Toyota U0198
2021 model year Highlander, Highlander Hybrid, RAV4, and RAV4 Hybrid; and 2021 model year RAV4 Prime vehicles equipped with Premium Audio (version 1383) may experience the followin
Quick answer
Toyota bulletin T-SB-0019-21 identifies U0198 as an intermittent DTC that may occur with certain Premium Audio head-unit software conditions. The supplied evidence does not establish a fault definition, driving risk, charging risk, or a vehicle-specific diagnosis for U0198 alone.
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 U0198 mean?
Toyota bulletin T-SB-0019-21 identifies U0198 as an intermittent DTC that may occur with certain Premium Audio head-unit software conditions. The supplied evidence does not establish a fault definition, driving risk, charging risk, or a vehicle-specific diagnosis for U0198 alone.
2. Technical explanation
NHTSA-hosted Toyota manufacturer communications T-SB-0019-21 Rev and Rev2 list intermittent DTC U0198 among conditions associated with a Denso-Ten Premium Audio head-unit software update. The bulletin also describes multimedia, Bluetooth, HVAC-display, meter-audio, and charging-screen concerns. The supplied evidence does not establish that every occurrence of U0198 has the same cause or that the code alone confirms a head-unit software issue.
3. What system is affected?
Premium Audio / multimedia head unit, based on the cited Toyota service bulletin.
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
- Intermittent U0198 may be present.
- The cited bulletin lists charging-icon operation concerns on the charging screen.
- Audio information may not display on the meter’s Audio tab.
- There may be a delay when turning off HVAC AUTO from the multimedia screen.
- HVAC settings may display differently after ACC-OFF.
- HVAC blower-motor operation may not display while AUTO is selected.
- Bluetooth may not reconnect after an Android Auto phone call.
- Bluetooth audio may play after connecting and disconnecting Android Auto.
6. Possible causes
- The verified bulletin associates the listed conditions, including intermittent U0198, with Premium Audio head-unit software addressed by Toyota’s Denso-Ten audio head-unit software update.
- Other causes of U0198 are 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 U0198 is intermittent and note any associated multimedia, Bluetooth, HVAC-display, meter-audio, or charging-screen behavior.
- Arrange Toyota dealer or qualified service evaluation and provide the applicable bulletin reference.
- Do not attempt high-voltage system repair based on this code or bulletin evidence.
10. Step-by-step troubleshooting
- Confirm the vehicle model year, model, market, Premium Audio equipment, and installed multimedia software version.
- Check whether Toyota T-SB-0019-21 Rev or Rev2 applies to the vehicle and reported condition.
- Use Toyota-approved service information to evaluate the multimedia head unit and determine whether the specified software update applies.
- Further diagnostic steps are not established by the supplied verified evidence.
11. When to contact service
Contact a Toyota dealer or qualified Toyota service provider if U0198 is stored or the associated multimedia, Bluetooth, HVAC-display, meter-audio, or charging-screen concerns occur.
12. What the service center may check
- Verify Premium Audio equipment and head-unit software version.
- Check for intermittent DTC U0198 and the other bulletin-listed intermittent DTCs.
- Determine applicability of Toyota T-SB-0019-21 Rev or Rev2.
- Perform the Toyota-specified Denso-Ten audio head-unit software update only if the bulletin applies.
13. Possible repair or resolution
- Toyota T-SB-0019-21 Rev and Rev2 describe an Audio Head Unit Software Update (Denso-Ten) for applicable vehicles and conditions.
- The supplied evidence does not establish the repair outcome for an individual vehicle.
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, NHTSA Manufacturer Communication 10201369, published July 9, 2021.
- Toyota T-SB-0019-21 Rev2, NHTSA Manufacturer Communication 10204562, published November 12, 2021.
16. Recall information
- No recall information was supplied or established by the verified evidence.
17. Official manufacturer information
Official NHTSA-hosted Toyota bulletin: https://static.nhtsa.gov/odi/tsbs/2021/MC-10204562-9999.pdf
19. Frequently asked questions
What does the supplied evidence say about U0198?
It lists U0198 as an intermittent DTC in Toyota T-SB-0019-21 Rev and Rev2, in connection with certain Premium Audio head-unit software conditions.
Does U0198 prove a charging-system fault?
No. The supplied evidence does not establish that U0198 alone identifies a charging-system fault.
Which vehicles are listed in the supplied applicability data?
US-market 2021 Prius Prime; US-market 2021–2022 Prius Prime; US-market 2021 RAV4 Prime; and US-market 2021–2022 RAV4 Prime are listed. The cited bulletin summary also references certain 2020–2022 Highlander, Highlander Hybrid, RAV4, and RAV4 Hybrid vehicles and certain 2021 RAV4 Prime vehicles equipped with Premium Audio.