P258B code meaning
Vacuum Pump Control Circuit A Range/Performance
Powertrain system Generic code P25xx codes Check engine light
What P258B means
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.
P258B at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.3 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P258B
- Engine, brake or stability warning lamp on
- Hard brake pedal, less brake assist
- Start-stop fault message
Common causes of P258B
- Most likelyWorn or failed electric vacuum pump
- PossibleLeaking hose or check valve that makes the pump run too long
- PossibleBlown pump fuse, spread terminals or poor ground
- Less likelyOutdated engine software controlling pump duty cycle
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Vacuum pumpVacuum lines
What each part of P258B means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 8B | The exact fault in that area. |
What to do next
- Note P258B 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 P258B
What does P258B mean?
P258B means "Vacuum Pump Control Circuit A Range/Performance". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P258B?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P258B fail an emissions test?
Yes, it can. P258B is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P258B to fix?
Difficulty: medium. A typical repair takes 0.3 to 3 hours of work. This is a job for a workshop.
Will P258B clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.