JL Slash 500 v1 Help

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You need to remove all of the power supply and output transistors. You already know that you'll have to replace all of the gate resistors for the power supply FETs. You now need to check all of the resistors near the output transistors. Are any out of tolerance?
 

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Here's the readings multimeter set to auto OHMS
R502- reads 75 (marked 75RO)
R503- reads 243 (marked 241)
R504- reads 001 maybe bc it's part of a different circuit? (marked 471)
R505- no reading (marked 470)
R506- reads 047? (marked 470)
R507- reads 470 (marked 471)
R508- reads 241 (marked 241)
R509- reads 75 (marked 75RO)
R510- reads 1566 (marked 682)
R511- reads 221 (marked 2210)
R512- reads 221 (marked 2210)
R513- No read (marked 101)

R599- No read (marked 470)

A little confusing to understand some of these readings, but not a single one looks like it is bad. I checked the gate resistors that are clearly blown and all read very near 0 ohms
 
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Quite a few look defective.

The last digit is the x10 multiplier for the ones without any letters. The other digits are the first numbers in the value.

If you haven't done so already, pull the output transistors. They could be skewing the readings.

The readings for the higher value resistors could be skewed by other components in the circuit. The one marked 682 (6.8k) is one example.

What do you mean by no reading? I'm assuming that the meter display didn't go blank.
 
Ok I pulled all the transistors including D600. And by no reading I mean i tried all the OHM measurement including auto and nothing happens but a 1 displayed on the left of the screen

R500- reads 24
R501- reads 24
R502- reads 75 so its good
R503- reads 241 so its good
R504- reads 001 so its bad?
R505- only reads 5.34 at 20M OHM so its bad?
R506- reads 47 so its good
R507- reads 470 so its good
R508- reads 240 so its good
R509- reads 75 so its good
R510- reads 6.77 at 20k so I assume its good??
R511- reads 221 so its good
R512- reads 221 so its good
R513- reads 3.89 at 20M OHM so its bad?
R514- doesnt read (the 1 stays on the left of screen) even at 20M OHM so its bad?
R515- 10 so its good
R516- 100 so its good
R517- 10 so its good
 
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If it was reading low in the circuit and it reads the same when you reinstall it, you don't need to replace it.

If it was reading high in the circuit with a steady reading, I'd suggest that you replace it.

Since you have to order others and the cost is insignificant (less than a nickel), there's really no reason to reinstall the old one.

When you reinstall them, use desoldering braid to desolder both pads. Add new solder to one pad. Heat the solder and slide the new resistor into the solder. Hold it in place and remove the heat. Then solder the other end.

Don't use the braid from radio shack unless you use flux with it. If you use their paste flux, the braid will work reasonably well but you'll have to clean up the area with acetone and cotton swabs because the flux makes a mess. Use the flux sparingly. If you buy braid from the same place where you get the other parts, buy braid that has flux in it.
 
I mean the amount of resistance in Ohms of each resistors (R600-R607) so I can order the right ones because I cant read them at all. Also can I order the transistors there, and are they all the same or are there specific ones for each spot? I assume Q504-Q507 are different from Q600-Q607 and D600
 
Ok the power supply FETs are IRFZ44N but its hard for me to tell which ones I need there are like 1000s of them on mouser electronics. on the resistor it says I(down arrow)R 512k 8T 4D

Can't find the IRF540 marked I(down arrow)R 513k BB 47

Can't find D600 its marked something506 SFI606G

Found the gate resistors (I think) CR1206-FX-47R0ELF Bourns Thick Film Resistors - SMD

Cant find the 101 marked resistor or 470 and 471
 
I don't know what you mean when you say the legs are bent but the center leg MUST be bent to allow the transistor to lay flat against the heatsink. See attached.

That 540 will work.

Don't install the outputs when you get them. You still need to do more troubleshooting but the resistors that you found defective needed to be replaced first.

When you get the new parts, install all of the gate resistors for the power supply and confirm that you read 90 ohms between the gate pads for each bank of 4 FETs. Then power the amp up and confirm that you read 4-5 volts DC on each of the gate pads.

If you haven't read the basic repair page, read it before you begin, especially the notes in the yellow box near the top of the page.
 
All of the legs are bent, not just the middle because I didn't do a good job removing the clips and I already removed the D600. Well I hope that these parts will cover it and I will keep updated on how it's going once the parts come in. Thanks for all the help man you really know your stuff, I couldn't have made it this far without you
 
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