B0105 code meaning
Sensor Cleaning Air Blower Actuator B Control Relay
What B0105 means
B0105 is the relay fault on the B side of the sensor-cleaning air supply. If B is a compressor rather than a small fan, as in Uber's patent where a compressor charges an accumulator and recharges once pressure drops to roughly 130–140 psi, the relay carries a sizable inrush current, and pitted contacts become the usual weak point. HELLA lists change-over and make relays for motors such as fans and names the checks: dropout voltage, contact drop, coil resistance. AUMOVIO stresses that air keeps a lidar usable in bad weather by blowing off droplets, so a stuck relay shows up first in rain. No carmaker has published B0105 or what B supplies.
B0105 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyEasy, DIY possible
- Typical labor0.2 to 1 hours
- Clears after repairWhen cleared with a scanner
Symptoms of B0105
- Blower or compressor B does not start, or will not switch off
- Droplets stay on sensor windows in rain
- Assistance functions drop out when a sensor is reported blocked
Common causes of B0105
- Most likelyContacts of relay B pitted by high motor or compressor inrush current
- PossibleRelay B coil or its suppression diode failed
- Less likelyCorroded relay socket or wrong relay type fitted
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Sensor cleaning air blower relay bRelay control circuitSensor cleaning air blower b
What each part of B0105 means
| B | Body system: airbags, seat belts, power seats, lights and climate control. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 05 | The exact fault in that area. |
What to do next
- Note B0105 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 B0105
What does B0105 mean?
B0105 means "Sensor Cleaning Air Blower Actuator B Control Relay". B0105 is the relay fault on the B side of the sensor-cleaning air supply. It is a generic code, so it means the same on every make.
Is it safe to drive with B0105?
Drive gently and only to a workshop. With B0105 the car can go into limp mode (reduced power) to protect itself.
Will B0105 fail an emissions test?
B0105 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 B0105 to fix?
Difficulty: easy. A typical repair takes 0.2 to 1 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will B0105 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.