Need Help Roland VS540i, Brand New Printhead Zero Nozzles firing after installing

[Jim Hancock]

I would change the meter to 200, 1 click clockwise from the setting you have now. You need to see numbers to test transistors. Refer back to post #2 on how to test transistors. You should read around 42 ohms. Your fuses should read 0 ohms or close to it. A blown fuse will read .0l, like in your meter pic.

 

[cornholio]

The pump should be replaced at around 200k pump cycles. I had machines with pumps around 200k still doing a good job for colors, but not for white anymore...
If some colors print and others don't, it could be the pump or the cap(alignment). (The cap doesn't disalign itself... so don't play with that, if you don't have to.)
If you use the expensive Roland parts, you should be ok replacing... if you use the Chinese copies, pray to whatever God you worship...
If i get called to a machine, where some DIY'er tried his luck with parts from Alibaba or Temu or other shady sources, I replace the parts for the customers sake. My hourly rates are too high to test these parts... it's for the good of the customer.

 

[damonCA21]

You also need to test both sides of the transistor as they can short and still give the 42/43 ohm reading

 

[damonCA21]

If you are in the UK I do board repairs and testing ( am in the UK too ) if you prefer someone else to have a look at it for you

 

[Myster Enigma]

Thanks guys I'll test the fuses on Monday and let you know. Really appreciate the advice. In terms of the replacement parts I did buy the cap station and pump from eBay. I'm sure they're not genuine but I have replaced capping stations a few times before without any issues. I'm still waiting for the pump. I ordered 2 printheads from Digiprint supplies and I asked them before hand if they were genuine and they said they were. I've replaced the one on my BN20 and it works perfectly.

 

[Myster Enigma]

If you are in the UK I do board repairs and testing ( am in the UK too ) if you prefer someone else to have a look at it for you

Ah that's great, I'd definitely like it tested just to be sure that everything is fine. May I ask if you can also repair and diagnose the issues to do with the air in the system if it's not an electrical issue. The address is in Birmingham. Please let me know. Thank you

 

[damonCA21]

I am in South Wales so you would need to send the board to me for testing but no problem to do this ( removing and refitting the board is an easy job ). I can help remotely with the air in the system if there arent any board problems

 

[Myster Enigma]

Hi guys, again thank you so much for your guidance so far. I managed to test the board today setting the multimeter to 200. So the 2 fuses read 0.00 on both of them. There were a total of 8 transistors. Many of them read 41.7 and 41.6 where as one read 42.0.

damonCA21 where you said "You also need to test both sides of the transistor as they can short and still give the 42/43 ohm reading" did you mean the 4 on the front and the 4 on the opposite side. Or do you mean the front of the legs as well as the back? I didn't remove the board from the printer so it's pretty hard reaching to get the back of each transistor.

Before I replaced the pump I ran one powerful clean and it did seem to work better. The ink in the tubes slowly moved towards the head. The pump had over 273099 uses so I decided to replace it today also

 

[Jim Hancock]

The transistors usually short out, so it doesn't matter which leads go to which outer legs. Your readings are all correct and in tolerance. Please post a current nozzle test.

 

[Myster Enigma]

Sorry I could only upload 5 photos so I have to open another chat box.

I replaced the pump, went into service menu and did a pump suction and pump release.

I also primed the dampers again from the 2 outlet holes for each damper. Now the colours are all completely solid leading to the head. In case there was any air left in the lines. I also noticed that one of the head ribbon cables (Second one) had a slight gap in the connector. It was like this before I replaced the printhead so I'm not sure if this is causing any issues.

So far I have replaced
4x Dampers
Printhead
Pump
Capping Station

I also had 3 printheads to test with. My old BN20's, My previous VS540i's (Which I don't even think was completely unusable even though it was leaking the nozzle tests were still of a good standard) and a brand new printhead. I tested 2 of them in the machine today after replacing the pump and re priming the dampers.

I am completely at a loss of what it could be. Hoping you guys have further suggestions as I don't understand what it could be.

 

[Myster Enigma]

The transistors usually short out, so it doesn't matter which leads go to which outer legs. Your readings are all correct and in tolerance. Please post a current nozzle test.

The nozzle tests are still the same. It is completely blank unfortunately.

 

[Jim Hancock]

You need to replace at least the one ribbon, as there are 4 traces I'm sure aren't making contact inside the head connector. Something melted the ribbon at that point. Here are p/n's -
1000006702 CABLE-CARD,29P1 256L BB HIGH-V 3 each
1000006703 CABLE-CARD,29P1 276L BBR HIGH-V 1 each

Digiprint carries them...

Do you have the service manual? There is a section on how to fold these ribbons.

 

[damonCA21]

OK this is the method I use to test the transistors. This rules out any shorting or out of spec problems


There are two types of head transistor ( the large ones connected to the heatsink ).
One turns the head on and one turns it off. They are marked C4131 and A1746.

BEFORE STARTING !!! unplug the printer from the wall and leave at least 15 minutes before testng. The printer does not have to be powered on to test them.

To test the C4131 transistor.

1. Turn the multimeter to diode test mode
2. Read across the two outside legs. The reading should show as around 43 ( it doesn't matter which probe is on which leg )
3. Put the black probe on the centre leg
4. Put the red on the left leg, it should read around 480 - 500
5. Put the red on the right leg, it should read around 480 - 500 as well

To test the A1746 transistor

1. Turn the multimeter to diode test mode
2. Read across the two outside legs. The reading should show as around 43 ( it doesn't matter which probe is on which leg )
3. Put the red probe on the centre leg
4. Put the black on the left leg, it should read around 480 - 500
5. Put the black on the right leg, it should read around 480 - 500 as well

If any readings are far out plus or minus the transistor is bad. If any show continuity the transistor has also gone bad and shorted. Note some multimeters will give different figures for the 43 test, but all transistors should match each other at a figure around this ( 40 to 50 ). If any are much higher or lower then they need to be replaced.

 

[Myster Enigma]

You need to replace at least the one ribbon, as there are 4 traces I'm sure aren't making contact inside the head connector. Something melted the ribbon at that point. Here are p/n's -
1000006702 CABLE-CARD,29P1 256L BB HIGH-V 3 each
1000006703 CABLE-CARD,29P1 276L BBR HIGH-V 1 each

Digiprint carries them...

Do you have the service manual? There is a section on how to fold these ribbons.

Thank you. I'll order this now. May I ask would that one ribbon cable make a difference meaning it can lead to all the nozzles not firing? I thought it would have been possibly one ribbon cable per colour channel. Yes I have the service manual so I may just replace all of the ribbon cables. Thank you

 

[Myster Enigma]

OK this is the method I use to test the transistors. This rules out any shorting or out of spec problems


There are two types of head transistor ( the large ones connected to the heatsink ).
One turns the head on and one turns it off. They are marked C4131 and A1746.

BEFORE STARTING !!! unplug the printer from the wall and leave at least 15 minutes before testng. The printer does not have to be powered on to test them.

To test the C4131 transistor.

1. Turn the multimeter to diode test mode
2. Read across the two outside legs. The reading should show as around 43 ( it doesn't matter which probe is on which leg )
3. Put the black probe on the centre leg
4. Put the red on the left leg, it should read around 480 - 500
5. Put the red on the right leg, it should read around 480 - 500 as well

To test the A1746 transistor

1. Turn the multimeter to diode test mode
2. Read across the two outside legs. The reading should show as around 43 ( it doesn't matter which probe is on which leg )
3. Put the red probe on the centre leg
4. Put the black on the left leg, it should read around 480 - 500
5. Put the black on the right leg, it should read around 480 - 500 as well

If any readings are far out plus or minus the transistor is bad. If any show continuity the transistor has also gone bad and shorted. Note some multimeters will give different figures for the 43 test, but all transistors should match each other at a figure around this ( 40 to 50 ). If any are much higher or lower then they need to be replaced.

Thank you. I'm going to do this again just to rule out any electrical faults for sure

 

[Myster Enigma]

OK this is the method I use to test the transistors. This rules out any shorting or out of spec problems


There are two types of head transistor ( the large ones connected to the heatsink ).
One turns the head on and one turns it off. They are marked C4131 and A1746.

BEFORE STARTING !!! unplug the printer from the wall and leave at least 15 minutes before testng. The printer does not have to be powered on to test them.

To test the C4131 transistor.

1. Turn the multimeter to diode test mode
2. Read across the two outside legs. The reading should show as around 43 ( it doesn't matter which probe is on which leg )
3. Put the black probe on the centre leg
4. Put the red on the left leg, it should read around 480 - 500
5. Put the red on the right leg, it should read around 480 - 500 as well

To test the A1746 transistor

1. Turn the multimeter to diode test mode
2. Read across the two outside legs. The reading should show as around 43 ( it doesn't matter which probe is on which leg )
3. Put the red probe on the centre leg
4. Put the black on the left leg, it should read around 480 - 500
5. Put the black on the right leg, it should read around 480 - 500 as well

If any readings are far out plus or minus the transistor is bad. If any show continuity the transistor has also gone bad and shorted. Note some multimeters will give different figures for the 43 test, but all transistors should match each other at a figure around this ( 40 to 50 ). If any are much higher or lower then they need to be replaced.

Also what do you make of the ribbon cables going into the printhead? If one fails doesn't that only affect one or 2 colours? I'm now deciding whether I need to spend money replacing them.

 

[Jim Hancock]

OK this is the method I use to test the transistors. This rules out any shorting or out of spec problems

Damon, good to know for other issues besides blowing fuses, I'll add to my testing procedure.

 

[damonCA21]

Yes if one fails it can effect the others

 

[Jim Hancock]

When in doubt about ribbons, replace. Probably the cheapest item in the electronics path for printhead issues.

 

[Myster Enigma]

Thank you guys. I just made the order. On digiprint for some reason there are 2 different prices for the same item. Can you guys check my order to see if it is correct. Also just for future reference as it is good for me to learn. With my bad ribbon cable is that melted part enough for it not to make contact with the printheads connectors? Again I assumed that if at least some of the gold connectors on the melted part made contact then it would be enough as there is some leniency.

Also what are the chances that this could have damaged/shorted my printheads. I always turned my printer completely off at the wall when installing the printhead.

Thanks again