OBD2 Car ScannerWhat does B1784 mean?
B1784 stands for Mirror Passenger Up Circuit Short To Battery. A body control module has found a fault in a comfort or safety system such as airbags, lights, doors, seats or climate control.
Body codes cover the airbags, seats, lights, doors and comfort systems. When the car's computer sees a reading outside its normal range, it stores this code and may turn on a warning light on the dashboard.
Common causes
- Damaged wiring or a loose connector (often under seats)
- Faulty switch, sensor or motor
- Low battery voltage
- Faulty body control module
What to do
- Read all stored and pending codes with a scanner. Several codes together often point to one cause.
- Note the freeze frame data (speed, temperature, load) recorded when the code was set.
- Inspect the wiring and connectors of the part named in the code for damage, corrosion or looseness.
- Fix the most likely and cheapest cause first, then clear the code and drive to see if it comes back.
Read this code from your own car
Plug in a cheap ELM327 adapter and the app shows every fault code, what it means and how to fix it.
Frequently asked questions
What does B1784 mean?
B1784 means “Mirror Passenger Up Circuit Short To Battery”. It belongs to the body system group: A body control module has found a fault in a comfort or safety system such as airbags, lights, doors, seats or climate control.
Is it safe to drive with B1784?
You can usually drive carefully for a short time, but fix it soon to avoid further damage or higher fuel use.
How do I clear B1784?
Fix the cause, then clear the code with an OBD2 scanner or app. If the fault is still there, the code will come back.
Related codes
- B1780Mirror Driver Down Circuit Short To Battery
- B1781Mirror Driver Down Short To Ground
- B1782Mirror Passenger Up Circuit Failure
- B1783Mirror Passenger Up Circuit Open
- B1785Mirror Passenger Up Circuit Short To Ground
- B1786Mirror Passenger Down Circuit Failure
- B1787Mirror Passenger Down Circuit Open
- B1788Mirror Passenger Down Circuit Short To Battery
Code meanings can vary by manufacturer. This page is general guidance, not a repair manual. Always confirm the cause before replacing parts.