U01BA code meaning
Lost Communication With Park Lock/Pawl Control Module
What U01BA means
With park-by-wire, an electric actuator drives the parking pawl into a toothed wheel on the transmission output; no cable links it to the selector, so the park lock module alone decides when the pawl may drop in, normally only at standstill because at speed it would just ratchet over the teeth. U01BA is set when the transmission or vehicle controller loses contact with this module. No manufacturer documents the code publicly. Ford, for one, has no separate unit: its 2024 OBD description monitors park-by-wire through the gear shift module and the transmission range control module, whose implausible data set non-MIL codes, and the transmission controller reads the park position sensors itself (P07B3–P07BD). Ford's 2012 description shows the general rule for such network codes: a message that does not arrive counts as lost communication (U0140), one that arrives with values out of range as invalid data (U0422). U019E differs, as it concerns the module that selects the whole transmission range. Without confirmed pawl position the car may refuse to leave Park, or it tells the driver to set the electric parking brake, and a warning to secure the vehicle appears. U04BD reports invalid data from the same module.
U01BA at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U01BA
- Vehicle will not shift out of Park or Park not confirmed
- Warning to secure the vehicle with the parking brake
Common causes of U01BA
- Most likelyConnector or wiring fault at the park lock actuator on the transmission
- PossibleLow 12 V supply, e.g. weak battery
- Less likelyPark lock control module faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Park lock moduleCAN bus
What each part of U01BA means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| BA | The exact fault in that area. |
What to do next
- Note U01BA and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U01BA
What does U01BA mean?
U01BA means "Lost Communication With Park Lock/Pawl Control Module". With park-by-wire, an electric actuator drives the parking pawl into a toothed wheel on the transmission output; no cable links it to the selector, so the park lock module alone decides when the pawl may drop in, normally only at standstill because at speed it would just ratchet over the teeth. It is a generic code, so it means the same on every make.
Is it safe to drive with U01BA?
Drive gently and only to a workshop. With U01BA the car can go into limp mode (reduced power) to protect itself.
Will U01BA fail an emissions test?
U01BA is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U01BA to fix?
Difficulty: hard. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will U01BA clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.