U0198
0 owner reports and 265 manufacturer filings across 44 model years from Ford, Lincoln, Mazda.
Where U0198 shows up
Source: NHTSA manufacturer communications and complaintsShowing the 25 model years where U0198 appears most; it is on file for 44 in total.
A model year appears here because the code is named in its record, not because every one of these vehicles sets it. Counts are mentions in the federal files, not failure rates — nobody publishes the denominator.
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U0198 by make
The same record, one make at a time: the model years, bulletins and owner reports that name U0198 on that maker’s vehicles.
What it gets filed under
265 manufacturer filings name U0198. Start with what the maker wrote down.
A code names the test that failed, not the part. A bulletin that names it is often a diagnosis someone has already written down — quote its number at the service desk.
Manufacturer filings that name it
Source: NHTSA manufacturer communicationsService bulletins and campaigns whose filed summary names U0198.
- SA-012-26b Service bulletin2026-04-18 · Electrical System
- Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One Time Passcode (OTP) may fail. • Connected Vehicle Remote functions may fail. • The following DTC's may be stored: B1252:87-8B:TCU - COMMUNICATION ERROR WITH CONNECTIVITY MASTER UNIT (CMU) • U0198:00-03:CMU - COMMUNICATION ERROR W
- SA-012-26a Service bulletin2026-03-04 · Electrical System
- This Service Alert supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-012/26 02/26/2026 DESCRIPTION Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One Time Passcode (OTP) may fail. Connected Vehicle Remote functions may fail. The following DTC'
- SA-012-26 Service bulletin2026-02-27 · Unknown Or Other
- This Service Alert supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-060/25 12/16/25 Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. Additional symptoms that may occur: Connected Vehicle One Time Passcode (OTP) may fail. Connected Vehicle Remote functions may fail. The following DTC's may be stored
- SA-060-25 Service bulletin2025-12-17 · Unknown Or Other
- Some customers may experience a message "TCU Malfunction. Have the Vehicle Inspected" in the instrument cluster. The following DTC's may be stored: B1252:87-8B:TCU - COMMUNICATION ERROR WITH CONNECTIVITY MASTER UNIT (CMU) • U0198:00-03:CMU - COMMUNICATION ERROR WITH EMERGENCY CALL UNIT/TELEMATICS COMMUNICATION UNIT
- SSM 48267 Service bulletin2019-10-17 · Electrical System
- Some 2018-2020 Ford and Lincoln vehicles equipped with a TCU may exhibit inoperative remote features via Ford Pass/Lincoln Way mobile app, incomplete user authorization and/or accessory protocol interface module (APIM) DTC U0198 or no modem electronic serial number (ESN) displayed. To correct this condition prior to programing remove the TCU fuse for 5 minutes then reinstall. Delete all previous s
- SSM 48260 Service bulletin2019-10-14 · Electrical System
- Some 2017-2020 Ford and Lincoln vehicles equipped with a TCU may exhibit inoperative remote features via Ford Pass/Lincoln Way mobile app, incomplete user authorization and/or accessory protocol interface module (APIM) DTC U0198 or no modem electronic serial number (ESN) displayed. To correct this condition prior to programming, remove the TCU fuse for 5 minutes then reinstall. Delete all previous
What U0198 means
Source: SAE J2012 / OBD-IIU0198 sits in the generic range of the OBD-II standard, so it means the same thing on every vehicle sold in the United States — but WhichTrim does not carry a definition for it and will not invent one. What is on this page is the record: who named it and on what.
A stored code names the test that failed, never the part that caused it. It is the starting point of a diagnosis, not its conclusion — the same code has several possible causes and the cheap one is not always right.
Common questions about U0198
Source: NHTSA files and the OBD-II standardCan I keep driving with U0198 stored?
Nobody can answer that from the code alone, and a site that does is guessing. A steady light means a fault was logged and the car should be checked soon; a flashing light means a severe misfire — slow down and get it seen as soon as possible, because severe misfire can quickly damage the catalytic converter. The safe read of this page is the mileage and the components, not permission.
Does a code mean the car is recalled?
No. Recalls are filed by campaign and matched by VIN, and none of them are triggered by a scan tool. If you want to know whether an open recall applies to one specific vehicle, check the VIN at nhtsa.gov/recalls — that is the only source that settles it.
Why do the counts here differ from other sites?
Because these are not estimates. Every number on this page is a count of documents in NHTSA's own files: manufacturer communications that name the code in their filed summary, and owner complaints that name it in the narrative. We do not model, weight or extrapolate them.
Will clearing the code fix it?
Clearing turns the light off and erases the freeze-frame data a technician would have used to work out what happened. If the condition is still there the code returns, usually within a few drive cycles, and the diagnosis now starts from less information than before.