Got a Bosch 18V battery that just won’t cooperate? One that doesn’t charge or work with any of your tools no matter what you try? Well, don’t replace it just yet.
There’s a chance you can bring it back to life. Let me guide you through three easy ways to reset your Bosch 18V battery and (fingers crossed) fix the problem.
If you want, you can first watch the short video I made about this topic. On the video, I demonstrated how to reset a 18V Bosch battery using 3 different methods.
First, I reset the battery with another healthy 18V Bosch battery. For the second method, I used another 18V to 20V tool battery from other brands to perform the reset. And for the last method, I reset it using a DC power supply.
How to Reset A Bosch 18V Battery
- Jumpstart It With A Healthy Bosch 18V Battery
The easiest fix often comes from using a sibling battery. If you’ve got another working Bosch 18V battery lying around, this trick might save the day. Here’s what you do:
Grab a working Bosch 18V battery and locate the positive (+) and negative (-) terminals on both the problematic and healthy batteries. They’re marked clearly beside each terminal.
Connect the healthy battery to the problem one using small parallel battery cables. Positive terminal to positive, negative to negative, like in the image below.
Hold the connection steady for about 15 seconds. That’s all the time it needs for a quick revival. Disconnect the cables, then pop the “fixed” battery onto the charger.
Check to see if the red light has disappeared. If the reset works, you’ll see the charging light turn green instead of red.
- Use Another Brand’s Battery
Don’t have a second Bosch battery? No worries. Batteries from other tool brands in the 18V to 20V range can work too. I tested it with a DeWALT 20V battery and it worked!
All that changes when you use a different battery is the brand itself, truly. The voltage is still the same, and that’s why the method is the same as last time too.
Identify the B+ (positive) and B- (negative) terminals on both batteries, just like before. Other brands might place them differently, so pay attention to the labels.
Use the same setup with parallel battery cables to connect the terminals (positive to positive, negative to negative). Hold the connection steady for about 15 seconds, then disconnect.
This might have given your Bosch 18V battery the nudge it needs to start charging again. Connect it to the charger to test it out.
- Use a DC Power Supply for a DIY Reset
If you don’t have any spare batteries at home, it’s not a problem. A DC power supply can step in for some extra help and do the job of an extra tool battery in this case.
Set your DC power supply to 18V and a current limit of 1A, as I’ve done down here. Don’t go any higher than those settings, since they match the exact needs of a Bosch 18V.
Attach the DC power supply to your battery after adjusting the settings. One lead of the power supply goes on the positive terminal, and its other lead on the negative terminal.
Let the connection sit for 15 seconds before turning off the power supply. Disconnect the power supply, then place your Bosch battery on its charger.
If all goes well, your battery should start charging like it was never problematic in the first place!
Conclusion
While these resets are effective for most batteries, they aren’t foolproof. Some batteries might be beyond saving, especially if they’ve been heavily used or stored improperly.
But hey, trying these tricks is a lot cheaper than buying a new battery. Give them a shot before spending any money on a replacement.
At the end of the day though, if your Bosch 18V Battery still refuses to charge or hold power after trying these tricks, it might be time to consider a replacement.
