MRCARTOOL B80 12V OBD2 Memory Saver with Voltage Display

Keep Vehicle Memory Settings Through a Battery Replacement

The B80 feeds power from a 12 V backup battery into the OBD2 port while the vehicle battery is out, so radio presets, seat positions, PCM and comfort settings stay intact however long the job takes. A charged 12 V backup battery is required.

16-Pin OBD2 Connection
Voltage and Current Display
Built-In 3 A Fuse
Reverse Polarity Protection

Key Features

Retains Key Settings

Keeps radio presets, seat positions, error codes, door, sunroof, window, air conditioning and infotainment settings during battery replacement or service.
Works With Ignition On or Off

The standard OBD2 connection supplies stable power regardless of ignition status, even through long service sessions.
Backup Battery Check

The built-in meter shows whether the backup battery has enough voltage before you start.
Reverse Connection Guard

If the clamps are connected the wrong way round, the display stays dark and no power is passed.
Fault Alarm

Abnormal battery voltage or current triggers an alarm and the screen flashes.

Highlights

B80 digital display showing voltage and current readings — Voltage and Current Readout

The digital display shows voltage and current changes while the cable is in use.

B80 control box with overcurrent, overvoltage and polarity protection icons — Circuit Protection

The 3 A fuse helps prevent damage to the tool and the vehicle ECU if a circuit fails.

Red and black insulated battery clamps with copper teeth — Insulated Clamps

Fully enclosed insulated clamp bodies with copper teeth and thickened springs.

More Specifications

Operating voltage range	10–14 V
Operating current	< 7 A
Operating temperature	-20 to 60 °C
Cable lengths	Clamp lead 0.5 m; OBD lead 0.4 m

What’s in the Box

B80 OBD emergency power cable
User manual

B80 main unit, retail box and user manual — B80 main unit and user manual.

How to Use

Prepare a backup batteryHave a sufficiently charged 12 V backup battery ready.
ConnectSwitch off the vehicle, plug the OBD2 end into the vehicle port and attach the clamps to the backup battery.
Check the indicatorsAfter a successful connection both LEDs light green and the display shows voltage.
Replace the batteryRemove the old vehicle battery and fit the new one; the settings are kept when you start the car.

Good to Know

Caution

While the battery is out, do not open the doors, turn on lights, start the vehicle, switch on any electronic device or touch the connections; doing so may damage the vehicle’s OBD connector.