Aiwa CDC-MP32 Headunit Unresponsive

[Perry Babin]

I think you misunderstand. Electrical leakage is tested by using a multimeter on ohms. With one polarity, you get an open circuit. Reversing the probes, you get something in the meg-ohm range, generally.

 

[D132]

Oh I thought you meant leaking as in how a capacitor leaks, I think I understand now
I don't read anything either way (could be user error though), should I put it back in and try it with the headunit on?

 

[Perry Babin]

No.

Do you have an auto-ranging multimeter?

Meter on ohms?

Do you have any other diodes on hand that you could use to confirm that you're not making any mistakes in testing?

 

[D132]

I have an auto multimeter as well, both multimeters showed nothing on either polarity

These are the other diodes I have, not sure which I could use

 

[Perry Babin]

I meant to say this earlier but 'showed nothing' isn't very meaningful and could be misinterpreted. When you give a meter reading, give the mode and the exact displayed reading (all digits).

If the meter reads the same as with the probes in contact with nothing but air, say it's an open circuit.

Check your meter. What does it read on resistance if you hold the probes together?

Auto-ranging or automotive meter? The meter you posted earlier (post #46) isn't auto-ranging.

 

[D132]

When I say “showed nothing” I’m referring to open circuit, sorry about that

Yellow meter reads 0.002 on the 2k ohm setting when probes are put together

This is the second meter I have
Auto as in auto-ranging
Reads 00.0 when probes together

 

[Perry Babin]

What does it read when you hold the probes with your fingers (probes not touching)?

 

[D132]

Both read about 1.6m ohm

 

[Perry Babin]

Check the diodes that you showed. Do any read like the diode in the DC player (always open circuit, no matter the probe orientation)?

 

[D132]

They all show open so it’s probably something I’m doing

 

[Perry Babin]

Try your other meter on the highest resistance range. Don't touch both probes at the same time. Pin one terminal against the workbench (or whatever) with one of the probes.

 

[D132]

Not really sure what you mean by that. Where would I put the positive probe? Also can I see if the diode is leaking with continuity? As in it would allow continuity one way and not the other, and if it’s leaking it would show both or neither?

 

[Perry Babin]

Continuity is generally useless for testing electronic components.

What are you unsure about?

 

[D132]

Where would I put the positive lead with the negative on workbench (unless you mean ground for the negative?)

Also I meant the diode setting, apologies

 

[Perry Babin]

Diode-check won't find leakage unless it's severe.

When I said to pin it against the bench, I simply meant to trap one lead of the diode between the meter probe and a non-conductive... anything. If you have alligator clips, use those to connect the meter to the diode.

 

[D132]

I think D713 is leaking as well as on the diode setting, it showed >1 one way and showed .801 the other way

D716 read .885 and D712 read .875, both only showed in one direction (other way was open circuit) if that is useful

 

[Perry Babin]

Those weren't taken on ohms/resistance.

 

[D132]

oh sorry
Ok so you want me to check the diode on highest resistance my multimeter can go to? (Yellow one)

 

[Perry Babin]

I want you to check the Zener on a meter that you can get normal readings on the other diodes. If it's a manual-ranging meter, check it on the highest resistance range.

 

[D132]

I was able to get the diodes in my parts bin to read resistance with the auto-ranging multimeter (some were too high for the yellow to read)

D712 still reads as open circuit on both multimeters