





๐ Keep your brakes sharp and your ride smooth with precision vacuum control!
The Semcto 28146SW Brake Vacuum Switch is a 12V automatic pressure switch designed to optimize electric brake booster vacuum pumps. Featuring a built-in check valve, it prevents pump overuse and extends pump life by activating between 0.04 and 0.06 MPa vacuum levels. Its preset, glued adjustment screw ensures reliable, maintenance-free operation, while screw terminal connectors guarantee a secure, leak-proof fit compatible with multiple pump models including AC Delco and 79 Corvette. Ideal for professionals seeking dependable brake vacuum management in custom or OEM setups.

| ASIN | B08QMLQC4C |
| Best Sellers Rank | #1,166,566 in Automotive ( See Top 100 in Automotive ) #2,622 in Air Conditioning Line Repair Tools |
| Brand | Semcto |
| Brand Name | Semcto |
| Coil Voltage | 12 volts |
| Connector Type | Screw |
| Contact Material | Copper Alloy |
| Contact Type | Normally Open |
| Customer Reviews | 3.4 out of 5 stars 162 Reviews |
| Manufacturer | Semcto |
| Maximum Switching Voltage | 12 volts |
| Minimum Switching Voltage | 12 volts |
| Model | 28146BP-002 |
| Mounting Type | Screw Mount |
| Number of Terminals | 3 |
| Operation Mode | Automatic |
| Part Number | 28146BP-002 |
| UPC | 709930351526 |
T**S
Works good
I'm using this as a brake vacuum boost pump switch on a custom electric vehicle and it works perfectly. I saw other reviews mention that theirs chatters but mine doesn't chatter at all and works perfectly so far.
A**.
The switches do not work. Iโm on my third one.
Iโve got three of these switches so far none of them work! When I hook them up, itโll work literally for a split second and shut off. If I take my feed wire and put it to the side of the switch for ground, everything works good. This third switch. I have never installed it put an old meter on it And the only place it functions correctly is on the inside. The body will not let it go to ground. I put my own meter on it and it does not show anything at all. The Amazon listing give something for troubleshooting, but it goes right to something with air-conditioning not even pertaining to this switch. Very frustrated.
C**N
East To Install Works Great
Works Great
D**R
Works til it doesnโt, Iโm on my third one..
I use it for a brakes on a cammed Silverado. Iโm on my third one of these due to them failing, I get about a month of use then they fail to work all together. There does not seem to be a better option as the ones from summit have similar issues. My suggestion is buy several, and prepare for sudden brake failure at all times lol!
E**N
Some issues
Like the other buyers said it chatters and won't shut off completely.i took it off the t bracket and mounted directly to my vacuum canister.works well so far but shut off at 14.i will try to readjust the pressure once I get a gauge back on.i tried grounding the body of the tee directly to the battery so it's not a ground issue.everything is wired correctly evident by it working as soon as I mounted it to the canister.
N**Y
High quality
Rigid product. Quality.
J**Z
As bad as other reviews
I read the reviews and saw that this didnt work for a lot of people. I decided to try it anyway because I need a 12v switch. This switch hasnt worked for me. When it seemed to function, there was a lot of chatter in the pump. From the product description, the turn on and turn off pressure are the same which is different from most switches. I added a valve check and the chatter continued. I bought a different valve check and the chatter continued. Then the switch just stopped working altogether. When the switch is connected, the pump doesnt turn on even when there is no vacuum. Unless you only need a switch for a day or two, I wouldnt buy this.
A**W
Preset too low
My vacuum pump runs, but not for long enough. My brakes barely stop me now. Switch not allowing enough vacuum
J**S
Works as it should
Excellent
N**L
Strong
Yes
L**C
good quality
Works well
G**.
dont work.
did switching part kept tripping. no use whatso ever. ups return system hopeless tried 3 times and still no joy
C**S
Read reviews first!!!!!!!!
Bought 2 units, both chatter the pump and relay because they do NOT brake the earth circuit enough to close the relay, I got done! Please read reviews first!
Trustpilot
1 month ago
2 weeks ago