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Blind Spot Monitor (BSM)

BSM (Blind Spot Monitor) is designed with latest microwave technology to warn driver of another vehicle or motorcycle approaching in adjacent lane, which is possibly in driver’s blind spot from side mirror.

System is activated automatically when you turn on ignition, LED indicator turns on if sensor detects another vehicle or motorcycle in adjacent lane coming closer. If you switch on turn signal on the same side when object is detected, LED indicator will flash, and you will also hear 3 beeps.


Working Voltage: 10V-16V

Max Working Current: 230mA

Work Temp: -40℃ – 80℃

Detection Rang: about 3mx8m

Parts & Wiring

System is composed of 2 microwave sensors, 1 control box, 2 LED Indicators, 1 buzzer., 2 sensor mounting brackets and wire harness. Wiring diagram is as follows,

Blind Spot Monitor (BSM)


  1. Sensors

Take off rear plastic bumper, install sensors at least 50cm high at two rear corners of car body. Top surface of sensor should be vertical to the ground, or better slightly face upwards up to 5 degree. Keep horizontal line “→“ on top surface parallel to the ground (it does no matter if arrow mark points towards front or back side), the line should form 32 to 35 degree angle to backside of car, i.e, 55 to 58 degree to car body direction. If corner area is not straight, you can move sensor a little bit inside to get a better location.

Note: The two sensors are interchangeable, but you need connect sensor on left side to L socket, and sensor on right side to R socket on wire harness.

If sensor stand is universal V shape metal

V shape stand has right angle between 32 to 35 degree, hold V shape stand with two sensor-fixing screw holes straight up and down and towards yourself, find a place where you can fit stand with surface vertical to the ground, or better slightly face upwards up to 5 degree, and where stand base with 3M sticker can give parallel touch to car backside to ensure sensor mounting angle, otherwise you may have to press or expand V shape with force to get desired sensor mounting angle. Screw sensor onto stand and stick stand with 3M sticker after cleaning the location area.

Installing for Blind spot monitor

If your metal stand is customized as per vehicle model

Mounting stand on certain defined position of vehicle, where sensor can get right angle, and normally there are holes to match holes in stand, mount stand on vehicle with screws.

The customized stand is made as per car model in China market, possibility exists that it may not fit in the same car model in your country.

Note: Make sure no metal object in front of sensor, and any metal parts around sensor such as cable, lamp housing, etc., should not be movable. Fix tightly those movable parts  around sensor to avoid moving in vibration. All cables around sensors should be extended and fixed tightly every 20cm with clip and tie.

  1. Control Box

Put control box in a convenient location for wiring at left side in driver’s compartment. In case you have to put control at right side and find cables for left sensor and LED indicator are not long enough, you can exchange left and right wiring for turn signal, sensor and LED indicator together.

  1. LED Indicators

1. Stick LED indicators inside close to side mirrors, where they can be observed without block.

2. If LED indicator of your system is built in side mirror or plastic garnish close to A pillar, replace original mirror or garnish to give a perfect OEM looking.

3. To replace original mirror, you need disassemble front door to wire cable.

  1. Buzzer

Hide buzzer inside driver’s compartment where it is hearable.

  1. Cable Connection

Red power cable to ACC+, Black cable to Ground, Yellow cable to left turn+, White cable to right turn+.

Connect cables to control box, matching colors and pin numbers

Function Testing & Finalizing Installation

  1. Turn on ignition to power on system, walk towards vehicle around 5m to 6m from back and side, LED indicator at the same side will turn on. Switch on turn signal at the same side, LED indicator will flash, and you will hear 3 beeps.
  2. Test from the other side.
  3. If you are using universal V shape sensor stand, double check sensor mounting angle, put AB

   glue on stand base and car body around 3M sticker, to ensure stand can be fixed tightly.

  1. Assemble car front doors if you have replaced side mirrors.
  2. Door-opening Collision Warning - when you park car to drop off passenger, and other car, motorcycle, bicycle or pedestrian comes over, LED will light on warning of door-opening collision.


  1. Keep bumper outside sensor clean from ice, snow, mud, etc..
  2. Avoid metal articles moving in trunk close to sensor.
  3. Heavy rain & thunder may affect performance.
  4. Concentrated grid transmission system or radar speed-detection on highway may affect performance.
  5. Relative speed lower than 0.25Km/h of approaching car may result in delay of warning.


OBD Functionwhen you put OBD plug into car OBD socket, system will start to work only when vehicle speed is more than 10Km/h. In this case, the foresaid Door-opening Collision Warning will be no more there. In most cases, we donot provide system with OBD function.


Disclaimer: BSM system is strictly a driving aid device, and should not be regarded as a substitute for safe driving practice. Using of it does not release drivers’ responsibilities to maneuver with common sense and caution. The owner shall not be entitled to claim from the manufacturer or its distributor, authorized dealers, retailers for any incidental and consequential damages or losses.