U025ELost Communication With Electronic Brake Booster Control Module A
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- Instead of a vacuum servo, an electronic brake booster uses a pedal travel sensor and an electric motor for the assist, which also lets regenerative braking be blended in, as in Bosch's iBooster. Mitsubishi documents U025E-00 in the engine control module of the Outlander PHEV from 2023, where it means lost contact with the EBA, the electric driven intelligent brake unit. With the power switch on and 10 to 16.5 V, no brake unit signals for 4 s set the code; it is stored when the fault recurs after the next start and belongs to the CAN monitor of the OBD drive cycle, which covers faults that light the check engine lamp. PHEV-ECU and ABS unit log their own timeouts. Ford shows the knock-on effect: a supply interruption at its booster lit the ABS and stability lamps (SSM 51374). Unit B is U025F.
- What you may notice
- Check engine lamp after repeated detection (Mitsubishi)
- Brake, ABS or stability warning lamps on
- Harder brake pedal or reduced regenerative braking
- Likely causes
- LikelyDamaged CAN wiring or connector between engine or brake controllers and the booster unit
- PossibleFault in the booster's power supply (high-current fuse, ground, 12 V battery)
- PossibleInternal failure of the electric brake unit
- RareFailure of the receiving engine control module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.