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Test for dead Bosch impact driver?

rick carpenter

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Can I test my Bosch 18v impact driver and my two slimpack batteries to see which is/are dead? I have a multimeter but I don't know how to use it for this. First one battery went out then almost immediately the second did... or so it seems. It's several years old and has lived a good but hard life, so I'd hate to invest in NOS batteries if the tool itself is no bueno.
 
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6PTsocket

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Can I test my Bosch 18v impact driver and my two slimpack batteries to see which is/are dead? I have a multimeter but I don't know how to use it for this. First one battery went out then almost immediately the second did... or so it seems. It's several years old and has lived a good but hard life, so I'd hate to invest in NOS batteries if the tool itself is no bueno.
What does the charger indicate? Isn't there an indication if the battery won't go to full charge?

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Sine Swept

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I wonder if they are so low they won't charge as the chargers do have certain circuits built into them. Even temperature can cause them not to charge.
 

jallyn

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I would charge them normally then check their voltage with your meter. Should be greater than the nominal 18-volts. Now run them in your tool even if they die right away. Check the battery voltage again. If it changed quite a bit and is now less than 18 volts you need new batteries. This is assuming there is nothing wrong with the tool.

If the tool is bad then the battery voltage would test good after trying to use them in the bad tool.

In other words good batteries have stable voltage above nominal even after limited use. Bad batteries either never charge to above nominal (18 volts) or drop quickly with limited use.
 

Voi

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I have a multimeter but I don't know how to use it for this. First one battery went out then almost immediately the second did... or so it seems. It's several years old and has lived a good but hard life, so I'd hate to invest in NOS batteries if the tool itself is no bueno.

You should find good tutorials for testing both the batteries and the charger on this page:

https://www.youtube.com/results?search_query=test+18v+battery+multimeter

Are the 18V Bosch batteries from your impact's generation not compatible with the current tools and vice versa?

My local Menards had a Hitachi angle grinder bare tool on their closeout shelf. No box or anything. I asked if I could bring one of my current batteries in and try it in the bare tool and they said yes. You might be able to get permission to bring your tool in and try a battery in one of the security strapped display models.
 

6PTsocket

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I wonder if they are so low they won't charge as the chargers do have certain circuits built into them. Even temperature can cause them not to charge.
He never said what happens on the charger. We don't know if they appear to charge or not. Then again, maybe his charger is AFU and that is the problem. First you try and charge the batteries. If they don't charge you have to isolate the problem. One battery NG, probably the battery. Two batteries NG probably the charger. If battery or batteries appear to charge, check with meter and see over 18 volts. If batteries check good, tool is bad. Short run time, batteries getting old.

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6PTsocket

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Can I test my Bosch 18v impact driver and my two slimpack batteries to see which is/are dead? I have a multimeter but I don't know how to use it for this. First one battery went out then almost immediately the second did... or so it seems. It's several years old and has lived a good but hard life, so I'd hate to invest in NOS batteries if the tool itself is no bueno.
Put the multimeter on DC volts l. If it has different DC ranges put it on the lowest one that is greater than 20 volts Make sure the red probe is plugged into the jack that says volts and ohms. Plug the black probe into the jack marked common. Now, touch the probes to the battery terminals. Don't worry which is which. One way you will get a - sign in front of the reading and with the probes reversed you will not. A charged battery will read well over 18 volts. If the battery is good it has to be the tool.

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OP
R

rick carpenter

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Thanks for the responses, I'll get back to y'all. FYI, the charger indicated they were charged. I thought maybe the batteries or maybe the tool, but I didn't think about the charger. Hmmm...
 
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JoJoSnap

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When was the last time u charged these batteries? I have the same kind.. i usually charge them occassionally


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dumper

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Oregon
take the tool over to Lowes, and "borrow" a battery from the display. This will rule out the charger and battery. I did this with mine, and found out it was the tool. Took it home, opened the tool up, and found out the motor was dead. Oh well.
 

6PTsocket

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If the charger says they are good the chances are that they are good. Now follow what I told you and measure that battery, . just to be sure. It is easy; give it a shot Looks like it is the tool.

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Danglerb

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Batteries have 3 or 4 connections these days, but if two of them don't have something like the normal rated battery voltage with a meter connected than the battery is bad. Use the voltage setting and don't short anything and nothing will bite you, put a probe on one of the connection and try all the rest. If nothing move to the next connection and try the rest again.

Charger says two batteries are good, doesn't look good for the impact.
 

6PTsocket

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Batteries have 3 or 4 connections these days, but if two of them don't have something like the normal rated battery voltage with a meter connected than the battery is bad. Use the voltage setting and don't short anything and nothing will bite you, put a probe on one of the connection and try all the rest. If nothing move to the next connection and try the rest again.

Charger says two batteries are good, doesn't look good for the impact.
Good advice.

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cheechi

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4Ah%20BAT620%20Lithium%20Battery_04.jpg

see the + & - labeled on the terminals? set the meter to V (with the - not the ~) and see what it reads across those.
 

6PTsocket

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OP, people have been telling you how to take this reading for days. Any hope here? After the picture it couldn't be any clearer. If you choose to go another route, please let us know and there will be no more suggestions.

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