P258B is the range/performance code for control circuit A of the vacuum pump: the pump is commanded, but its monitoring feedback or the vacuum it produces does not fit. Ford's 2018-2019 hybrid OBD summary sets it from the brake module when the monitoring line sits outside 1.3-5.0 V with the relay off, or below 250 mV for 1 s with the relay on. FCA case S1805000006 for 2017-2020 Pacifica, Cherokee, Wrangler, Gladiator and Ram 1500 links P258B, often with ABS code C1252, to pumps that cannot keep enough vacuum and asks for checks of fuses, terminals, hoses and check valves plus a PCM update from 2019. Audi's Q3 bulletin 2072305 (2021-2024) traces P258B00 to a blown pump fuse after the ABS connector had been unplugged while the engine was running. The brake pedal may feel hard.
Medium severity. Can I keep driving?If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
Symptoms
- Engine, brake or stability warning lamp on
- Hard brake pedal, less brake assist
- Start-stop fault message
Most likely causes
- Worn or failed electric vacuum pump
- Leaking hose or check valve that makes the pump run too long
- Blown pump fuse, spread terminals or poor ground
- Outdated engine software controlling pump duty cycle
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It affects emissions.
What each character of P258B means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- 5: Speed and idle
- 8B: Specific fault in that system
Frequently asked questions
Can I keep driving with code P258B?
If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
What causes code P258B?
The most common causes are: worn or failed electric vacuum pump; leaking hose or check valve that makes the pump run too long; blown pump fuse, spread terminals or poor ground.
Related codes
- P258AVacuum Pump Control Circuit A/Open
- P258CVacuum Pump Control Circuit A Low
- P258DVacuum Pump Control Circuit A High
- P25EFVacuum Pump Control Circuit B Range/Performance
- P0556Brake Booster Pressure Sensor Circuit Range/Performance
Sources
- fordservicecontent.com: OBDSM1901 HEV
- static.nhtsa.gov: MC 10173320 9999
- static.nhtsa.gov: MC 10247204 0001
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.