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Does the battery need to be disconnected during brake work?

Just had my tires replaced and brake pads replaced and rotor resurfaced. The battery was disconnected during the time the car was in the shop. I was just wondering if this is normal? I would not have thought it was necessary but then I don’t know much about working on cars. THanks for any help.

Not usually. But some shops make a habit of disconnecting the battery whenever they service a vehicle.


Tester probably has the right reason. There are many repairs that require it to reset the car’s computer and others that require it for safety reasons. The shop SOP might be to disconnect it every time just to keep things simple and error-free.

When I read instructions on most repairs, the 1st step is always to disconnect the battery. For most repairs (brakes) this is not necessary but I guess it is part of the CYA in the manual. I guess shops follow that too.

Disconnecting the battery is not necessary.

In my opinion… if the repair doesn’t call for the battery to be disconnected then don’t do it. Otherwise you are just asking for trouble by disconnecting every battery that comes into your shop. You risk losing the customer’s settings for the radio, power seat memory, and other electronic devices.

On GM vehicles if the customer doesn’t have the unlock code for the radio they have to make a trip to the dealer to get the radio unlocked. Is the shop that disconnected the battery going to pay the fee to unlock the radio?

Unless the repair calls for the battery to be disconnected, I will not disconnect a battery while the car is in my shop.

Do you have ABS? With ABS, the ABS module has to be disconnected before the brakes are bled. I don’t know if disconnecting the battery qualifies as disconnecting the ABS module connector, but if it does, it is no doubt easier to disconnect the battery than it is to find and disconnect that ABS module.

It depends on the car. My 2005 Accord has ABS and I don’t have to disconnect the battery to bleed the brakes.

There are small power packs available that can supply memory power while the battery is disconnected but you may already be aware of that.