Ryobi 4v cordless drill

[spike1947]

Hi
Sorry not been into electronics for quite awhile so a bit slow !.
Have a Ryobi 4v cordless drill, problem not charging, voltage at input 6.2v!, what do I have to check in between ?.
have done a schematic, but not sure, if it is the correct way !.
Have done a schematic !
cheers
Spike

 

[spike1947]

Did a test from neg lead onto board and first pin on D1 and getting 6.7v then tested the other side of D1 , no voltage !,

 

[Bluejets]

Usually because the charger detects a dead battery. Test should be done with one of known good condition.

 

[Delta Prime]

Did a test from neg lead onto board and first pin on D1 and getting 6.7v then tested the other side of D1 , no voltage !,

What were you expecting? That's normal
You're using common ground. First pin on D1 is the anode(+) you're supposed to have voltage on there. The other side of D1 is the cathode(-) which is where your negative lead is connected to(common ground)so you just shorted your test leads....
The component circled in yellow does not look right to me, no gaps on a T-92 style package...
Didn't bother to look at your schematic....

 

[Bluejets]

Didn't bother to look at your schematic....

Looks incorrect to me anyhow........ (charge input??)

 

[Bluejets]

The other side of D1 is the cathode(-) which is where your negative lead is connected to(common ground)

No it is not.............

 

[davenn]

Have done a schematic !

The Q2 2N3905 is a PNP transistor, NOT a Schottly Rectifier

 

[Delta Prime]

Let that be a lesson to everyone, you have to see the schematics before you comment sorry I don't open PDFs,

 

[spike1947]

Usually because the charger detects a dead battery. Test should be done with one of known good condition.

Hi
Tks for your reply, yes did fit another Litho batt, was showing @3.95v !.

cheers
Spike

 

[spike1947]

Looks incorrect to me anyhow........ (charge input??)

Hi
Tks for your reply, getting 6.7v at the charger input at the board !.

cheers
Spike

 

[spike1947]

Let that be a lesson to everyone, you have to see the schematics before you comment sorry I don't open PDFs,

Hi
Made the schematic in Eagle, but it won't let me upload that !.
cheers
Spike

 

[spike1947]

The Q2 2N3905 is a PNP transistor, NOT a Schottly Rectifier

Hi
Tks for your reply, yes sorry my bad, I don't know how I named that incorrect.

cheers
Spike

 

[spike1947]

Looks incorrect to me anyhow........ (charge input??)

Hi again
Can you pls tell me what you think is incorrect ?.

cheers
Spike

 

[spike1947]

Hi
I have this in a "Eagle" schematic, but the site won't let me upload that type of file !.

Spike

 

[bertus]

Hello,

Make a screenshot of your schematic and upload the picture.

Bertus

 

[spike1947]

What were you expecting? That's normal
You're using common ground. First pin on D1 is the anode(+) you're supposed to have voltage on there. The other side of D1 is the cathode(-) which is where your negative lead is connected to(common ground)so you just shorted your test leads....
The component circled in yellow does not look right to me, no gaps on a T-92 style package...
Didn't bother to look at your schematic....
View attachment 64348

Hi
1: Thanks for your reply, not sure what I was expecting tbh, well I thought I would of got a full charger voltage reading or near enough !.

2: Sorry I don't understand what you are meaning "The component circled in yellow does not look right to me, no gaps on a T-92 style package".

3: Can you say why didn't didn't bother to look at my schematic ?.

cheers
Spike

 

[spike1947]

Hello,

Make a screenshot of your schematic and upload the picture.

Bertus

Hi
Yes tks for that.

Spike

 

[spike1947]

Hi
Yes tks for that.

Spike

 

[Bluejets]

Can you pls tell me what you think is incorrect ?.

Diodes, Led and transistors appear to be a-up as well as pos/neg from input.

More recent posts suggest the schematic is your interpretation so that explains many of the errors.

 

[spike1947]

Diodes, Led and transistors appear to be a-up as well as pos/neg from input.

More recent posts suggest the schematic is your interpretation so that explains many of the errors.

Hi
Tks for your reply, I have done the schematic had per what is on the pcb, will check again for any errors.
cheers