Need electronics genius.

[TimWafer]

I know very little about electronics but once fixed a circuit board in my Genie manlift by replacing a diode that had blown. Skip ahead 8 years and Im again facing a similar problem in the same manlift. This circuit board is the speed controller 36557GT for the boom functions. I again see a blown component on it. They want in the neighborhood of $800 for this little control. I figure Ive got nothing to lose by trying to fix it. My problem is i dont know how to ID the components. My guess is this is a resistor. I can see 4 bands on it. Im thinking you read it from left to right in the picture. Its about 15mm long and maybe 6mm in diameter. Im confused as to how to read it if it is indeed a resistor. Looks like brown, brown, silver or white, and black or brown at the end. I can find no schematic for this little board to help ID it. Can anyone enlighten me or offer any help? Thanks

 

[olddavid]

Unfortunately, that resistance value is unreadable. If you can find a parts list for the board you could find out what value it's supposed to be. Sometimes you can find schematics online. Or, if you have another unit with the same board you can look at you could find out. Changing it might fix it. Often parts are engineered for the maximum allowable current and it may have just gotten hot too many times. It's also possible something else failed that made it fail. It's worth a shot, though. Good luck. PS not a genius but 38 years in the electronic industry.

 

[Brownie450]

If you can lift one end of the resistor & get a measurement
with your Ohm meter, quite often the component will go
back to the resistance originally set.
Could be a capacitor, also, but likely a 2 to 5 Watt resistor.
See if you can follow the traces that go to this resistor to
find a component that shorted & caused the overheating.
Could be a diode shorted or a capacitor.
See if there is a TO 220 SCR or transistor that might look
a little iffy.
Jim

 

[Brownie450]

Look for an LM7806 or LM 7812 that looks burned.
They are voltage regulators & have been known to
go bad.
Jim

 

[Janicholson]

Black=0
Brown=1
red=2
orange=3
yellow=4
green=5
blue=6
violet=7
grey=8
White=9
1st band is a digit, second band is a digit, third band is the # of zeros, fourth band is % of tolerance no band 20%, silver 10%, gold 5%
one simple chart
I agree it is probably toasted such that the colors are burnt. Jim

 

[Fixingfarmer]

I believe that silver stripe on the end denotes which way it flows through and that it’s a diode thick silver stripe toward negative

Find a like component nearby and check with the ohm meter and figure out what it may be resistor or diode

 

[wore out]

I believe that silver stripe on the end denotes which way it flows through and that it’s a diode thick silver stripe toward negative

Find a like component nearby and check with the ohm meter and figure out what it may be resistor or diode

Note the marking of "R21" next to one of the component's little legs, the "R" designation makes it nearly 100% certain it is a resistor..

 

[Fixingfarmer]

Note the marking of "R21" next to one of the component's little legs, the "R" designation makes it nearly 100% certain it is a resistor..

I agree that’s also likely but check it. Genie and jlg are some of the worst offenders at not following the rules.

At the very least we are talking a rather high resistance resistor with an 8 to start the ohm reading formula. Or essentially nothing is getting through. Check if you have a diode test on your meter and there is a similar one somewhere on that board. Should beep one way showing continuity and not the other. I’m not saying I’m not wrong but check it.

Then see if you can figure out what it controls…

 

[olddavid]

Black=0
Brown=1
red=2
orange=3
yellow=4
green=5
blue=6
violet=7
grey=8
White=9
1st band is a digit, second band is a digit, third band is the # of zeros, fourth band is % of tolerance no band 20%, silver 10%, gold 5%
one simple chart
I agree it is probably toasted such that the colors are burnt. Jim

Yeah, I don't think he's going to figure out the value from the colors. I ran into a resistor that didn't look burnt but it had changed the band colors enough to give a misleading color code reading.

 

[wore out]

Yeah, I don't think he's going to figure out the value from the colors. I ran into a resistor that didn't look burnt but it had changed the band colors enough to give a misleading color code reading.

Absolutely.

 

[YosmiteSam]

I see a wide gray band, a narrow gray band and a narrow white band.

That comes to 88 Gigaohms. Since it's a three-band resistor, the tolerance would be ±20%. but I do see the remainder of a tolerance band there.

That value is hard to imagine being used in a circuit board of that type. Suppose that before being burnt it had two black bands followed by a white band. I can imagine that would be what it might have looked like before being burnt out.

A resistor with two black bands followed by a white band is a 0 ohms resistor which is essentially a jumper wire. Try replacing it with a wire, any wire which will fit into the holes on the circuit board.

 

[MarkB_MI]

The actual resistance is unreadable. The wattage can be determined by size. But it's likely there's at least one other fault in the controller or lift that caused it to blow. Note that you might replace the controller with a new one only to have it blow again. Your best bet is the dig up a schematic of that board. The schematic will tell you the actual value and it will also tell you what the component is connected to so you can figure I why it blew.

You might be able to find something at this site:

Genie Schematic & Manual Main Index

 

[TimWafer]

Black=0
Brown=1
red=2
orange=3
yellow=4
green=5
blue=6
violet=7
grey=8
White=9
1st band is a digit, second band is a digit, third band is the # of zeros, fourth band is % of tolerance no band 20%, silver 10%, gold 5%
one simple chart
I agree it is probably toasted such that the colors are burnt. Jim

If it is a resistor, am I looking at it in the right direction? Which end do you start at? I read one place you start at the band closest to the end which appears to me to be the wide brown band. Another place said if there is a wide band it should be at the right end or last. Which is it?

 

[TimWafer]

The actual resistance is unreadable. The wattage can be determined by size. But it's likely there's at least one other fault in the controller or lift that caused it to blow. Note that you might replace the controller with a new one only to have it blow again. Your best bet is the dig up a schematic of that board. The schematic will tell you the actual value and it will also tell you what the component is connected to so you can figure I why it blew.

You might be able to find something at this site:

Genie Schematic & Manual Main Index

Below is a picture of the whole board. There isnt another component that looks even close on it. I also dont see any other part that to my untrained eye looks bad. I have been looking for a schematic for this board to no avail so far. i will continue my search. It apparently is used in other brand lifts other than Genie. It does say R21 next to the burnt component which also prompted me to think it was a resistor.

 

[MarkB_MI]

Below is a picture of the whole board. There isnt another component that looks even close on it. I also dont see any other part that to my untrained eye looks bad. I have been looking for a schematic for this board to no avail so far. i will continue my search. It apparently is used in other brand lifts other than Genie. It does say R21 next to the burnt component which also prompted me to think it was a resistor.

Below is a picture of the whole board.

That picture is MUCH better. I think I can make out the color code now. Reading from right to left, it looks like the code is brown-brown-silver-gold. If correct, this would be 11 x .01, or 0.11 ohms. The gold band indicates 5% tolerance. You can determine the power (watt) rating by measuring the resistor's dimensions.

Most likely it's some sort of current shunt that's in series with whatever device this board is driving. If you look on the back side of the board, you should be able to trace out what the resistor is connected to. My guess is you'll find that one of those adjacent colored wires is connected to the resistor. Figure out where the wire goes and you might find another problem outside the circuit board.

 

[TimWafer]

The actual resistance is unreadable. The wattage can be determined by size. But it's likely there's at least one other fault in the controller or lift that caused it to blow. Note that you might replace the controller with a new one only to have it blow again. Your best bet is the dig up a schematic of that board. The schematic will tell you the actual value and it will also tell you what the component is connected to so you can figure I why it blew.

You might be able to find something at this site:

Genie Schematic & Manual Main Index

Below is a picture of the whole board. There isnt another component that looks even close on it. I also dont see any other part that to my untrained eye looks bad. I have been looking for a schematic for this board to no avail so far. i will continue my search. It apparently is used in other brand lifts other than Genie. It does say R21 next to the burnt component which also prompted me to think it was a resistor.

That picture is MUCH better. I think I can make out the color code now. Reading from right to left, it looks like the code is brown-brown-silver-gold. If correct, this would be 11 x .01, or 0.11 ohms. The gold band indicates 5% tolerance. You can determine the power (watt) rating by measuring the resistor's dimensions.

Most likely it's some sort of current shunt that's in series with whatever device this board is driving. If you look on thback side of the board, you should be able to trace out what the resistor is connected to. My guess is you'll find that one of those adjacent colored wires is connected to the resistor. Figure out where the wire goes and you might find another problem outside the circuit board.

How do you know which end to start reading the color codes from? I seem to be getting conflicting answers to this.

 

[MarkB_MI]

Below is a picture of the whole board. There isnt another component that looks even close on it. I also dont see any other part that to my untrained eye looks bad. I have been looking for a schematic for this board to no avail so far. i will continue my search. It apparently is used in other brand lifts other than Genie. It does say R21 next to the burnt component which also prompted me to think it was a resistor.

How do you know which end to start reading the color codes from? I seem to be getting conflicting answers to this.

How do you know which end to start reading the color codes from? I seem to be getting conflicting answers to this.

There are a couple of things to tip you off. First, one band is thicker than the others, which means it's the most significant digit. Also, silver and gold are never used as digits, only as multipliers or tolerance markers. I can't actually tell that the last band is gold, but it's certainly not silver so it's most likely gold. Another tip-off is the large physical size of the device, telling me it has a high wattage rating, which means it must have fairly low resistance, probably an ohm or less.

 

[TimWafer]

I know very little about electronics but once fixed a circuit board in my Genie manlift by replacing a diode that had blown. Skip ahead 8 years and Im again facing a similar problem in the same manlift. This circuit board is the speed controller 36557GT for the boom functions. I again see a blown component on it. They want in the neighborhood of $800 for this little control. I figure Ive got nothing to lose by trying to fix it. My problem is i dont know how to ID the components. My guess is this is a resistor. I can see 4 bands on it. Im thinking you read it from left to right in the picture. Its about 15mm long and maybe 6mm in diameter. Im confused as to how to read it if it is indeed a resistor. Looks like brown, brown, silver or white, and black or brown at the end. I can find no schematic for this little board to help ID it. Can anyone enlighten me or offer any help? Thanks

View attachment 114944

There are a couple of things to tip you off. First, one band is thicker than the others, which means it's the most significant digit. Also, silver and gold are never used as digits, only as multipliers or tolerance markers. I can't actually tell that the last band is gold, but it's certainly not silver so it's most likely gold. Another tip-off is the large physical size of the device, telling me it has a high wattage rating, which means it must have fairly low resistance, probably an ohm or less.

When I google which way to read the bands, I keep getting answers that a wide band is normally the last band on a resistor. This is whats really confusing me. I see what you mean about the silver and gold being at the end though as well. But then there's the problem as to what the colors really were since its burnt. Looking at them in person , I can see them being multiple different colors before being burnt.
This controller controls a proportional solenoid that controls hydraulic flow to regulate boom speed and is supposedly 24 volt DC.

 

[JMOR]

I have hundreds of resistors & can safely say that they do not fit all the "stuff" stated in this array of postings. If I were you, I would conclude that "my 'guess' is as good as theirs".

 

[Janicholson]

When I google which way to read the bands, I keep getting answers that a wide band is normally the last band on a resistor. This is whats really confusing me. I see what you mean about the silver and gold being at the end though as well. But then there's the problem as to what the colors really were since its burnt. Looking at them in person , I can see them being multiple different colors before being burnt.
This controller controls a proportional solenoid that controls hydraulic flow to regulate boom speed and is supposedly 24 volt DC.

Use a bit of 400grit paper on the resistors bands (remove it from the board and observe the opposite side, then polish it a bit. Another idea is to purchase a 30 + watt rheostat (variable resistor) that goes from zero ohms to about 200. Splice ti into the circuit with 16 cauge wires. Starting at 200 Ohms, and turning ti toward zero slowly will potentially get it operating. Jim