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Discussion Starter #161
One other resistance measurement I liked you to take is when the RST module is powered down measure between any of the resistor ends with 12V label and ground. Take this measurement when the Y connector is plugged in and also when it's unplugged. The 12V label point is the common 12V pullup voltage on all the switch input line resistors.
I have the N52 with me, so at the moment I can take any measurements that do not require hooking N52 up to the car. There is no continuity from resistor ends with 12V label to ground (X10). But I have something interesting - there is continuity to ground (X10) from resistor end where you had put the switch ID labels for these two: 19 right bow lock and 26 ST compartment right cover closed. Resistance was 0.2Ohms. There is no continuity to ground for any other pins with ID labels. If I measure resistance from ID label 20 then there is resistance to ground (X10) 845 Ohms, some other have similar resistance, some have significantly higher resistance.
 

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That is interesting, this would suggest the Y19 and Y26 diodes are shorted to ground. The chip side of the board and diode closest to the Y connector. There should not be short between the labeled end of the resistor and ground. If possible desolder the diodes and check if the short is gone, if still there it's possible the cap is shorted to ground but I would first suspect the diode. Y26 may be shorted to ground but the condition checked for both the open and closed ST results is the switch being closed both times so check the diode there too. I would also think that there would be short on Y27 soft top open switch because it measured 0V when the top is up, should be 12V so need to recheck this one.

2612507
 

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Discussion Starter #163
That is interesting, this would suggest the Y19 and Y26 diodes are shorted to ground. The chip side of the board and diode closest to the Y connector. There should not be short between the labeled end of the resistor and ground. If possible desolder the diodes and check if the short is gone, if still there it's possible the cap is shorted to ground but I would first suspect the diode. Y26 may be shorted to ground but the condition checked for both the open and closed ST results is the switch being closed both times so check the diode there too. I would also think that there would be short on Y27 soft top open switch because it measured 0V when the top is up, should be 12V so need to recheck this one.

View attachment 2612507
I desoldered diode DI019 and the short is gone, now resistance measures 1120Ohms. Checked diode with multimeter both ways it shows 0.002, which is not ok for diode. So it seams we have solved two more problems.

Checked short for Y27 and "unfortunately" there is no short to ground, resistance is 1120Ohms.

Do you think I can hook up the module to car without DI019 to measure ZTX751 transistor voltage and make other measurements you and Bob suggested?
 

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I desoldered diode DI019 and the short is gone, now resistance measures 1120Ohms. Checked diode with multimeter both ways it shows 0.002, which is not ok for diode. So it seams we have solved two more problems.

Checked short for Y27 and "unfortunately" there is no short to ground, resistance is 1120Ohms.

Do you think I can hook up the module to car without DI019 to measure ZTX751 transistor voltage and make other measurements you and Bob suggested?
What about Y26, probably the same, a shorted diode. Not sure what's going with Y27, recheck when you get the module in the car. Yes, you can hook up the module without the diode(s) and measure the 751 transistor voltage and other measurements. Without this/these shorted switch signal lines you should see more progress with the top operation.
 

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Discussion Starter #165 (Edited)
I soldered two replacement diodes in DI019 and DI026. From raised and locked ST position with S84, both rear bow locks unlatches, bow pops out and rises 1/4 of the way, but just the left side and when trying to close with S84, then it looks like right side is going up a bit, but definitely not down, it seams that each side is going in different direction.

Here are the measurements. Y connector unplugged there is 11.5V on all pins in both rows, but now when Y connector is plugged in voltage is even less (battery was fully charged), please see pictures for results. I also measured ZTX751 and all 5V regulators, please also see pictures. Labels for 5V regulators are labeled in exactly the same order as 5V regulator legs. 5V regulator results are not what I expected at all.

N52 in diagnostic mode when ST lowered now have such errors: 2,3,4,5,11,12,20. Which means that 7 (Limit switch, right locked, soft top fabric bow) is gone, most likely because diode replacement worked and now it also does not measure 0V, but some voltage when ST is open, so that is progress. I'm glad that it wasn't microcontroller gone "crazy", so there is hope to fix all this as it can be just "one" component. However error 11 (Limit switch, right front locked, soft top) is new.

I think low voltage and Y inputs 20,21,25,26,27 if fixed there could be some progress, Are there some other points I could measure to make sure there is no permanent short to ground for these inputs?

Y connector input 1 of 2 with labels.jpg Y connector input 2 of 2 with labels.jpg 5V regulator and ZTX751.jpg 5V regulators.jpg
 

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I soldered two replacement diodes in DI019 and DI026. From raised and locked ST position with S84, both rear bow locks unlatches, bow pops out and rises 1/4 of the way, but just the left side and when trying to close with S84, then it looks like right side is going up a bit, but definitely not down, it seams that each side is going in different direction.

Here are the measurements. Y connector unplugged there is 11.5V on all pins in both rows, but now when Y connector is plugged in voltage is even less (battery was fully charged), please see pictures for results. I also measured ZTX751 and all 5V regulators, please also see pictures. Labels for 5V regulators are labeled in exactly the same order as 5V regulator legs. 5V regulator results are not what I expected at all.

N52 in diagnostic mode when ST lowered now have such errors: 2,3,4,5,11,12,20. Which means that 7 (Limit switch, right locked, soft top fabric bow) is gone, most likely because diode replacement worked and now it also does not measure 0V, but some voltage when ST is open, so that is progress. I'm glad that it wasn't microcontroller gone "crazy", so there is hope to fix all this as it can be just "one" component. However error 11 (Limit switch, right front locked, soft top) is new.

I think low voltage and Y inputs 20,21,25,26,27 if fixed there could be some progress, Are there some other points I could measure to make sure there is no permanent short to ground for these inputs?

View attachment 2612585 View attachment 2612586 View attachment 2612587 View attachment 2612588
Thanks for these measurements I'll take a look at them and get back. For the bow sides seeming to go in a different direction the only thing that comes to mind is the hydraulic lines being mixed up, they're numbered so check the line connections, especially the side that seems to be going in the unexpected direction.
 

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Looking at the voltages I'm surprised the controller works at all. For the very low switch signal lines pullup voltage when the Y connector is plugged in the controller is never going to see the correct switch open/closed status. I would do a couple of thing for this based on the voltages you measured.
With the controller powered down and the Y connector connected measure resistance from the common 12V pullup voltage side of the resistors to ground, use any of the resistor ends with the 12V label or collector of the 751 transistor and measure from there to ground. Want to see what the load is the ZTX 751transistor is having to drive. If the resistance value seems reasonable then the second thing I would suggest doing is replacing this ZTX751 transistor. Seeing the same voltage on the base and collector of the 751 transistor makes me think there's a problem with the transistor.

The 2950A CZ5.0 voltage regulator output doesn't look good either, would expect this to be 5V. For this I would also check the resistance to ground from the output pin and if reasonable then replace the voltage regulator. The dark area around this device from high heat makes this device suspect or a high load from a shorted device it powers.

Really need to have decent voltage levels for the switch open/closed lines and 5V from the regulator to get things in better shape.

It is good to hear there is some progress being made, such as bow attempting to raise although I'm not sure how anything works with the low pullup voltage and VR output. Any luck with opening the soft top, does the compartment cover open? The other devices you measured look like power transistors (LP357Z) and I'm not certain those voltage indicate a problem.
 

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Discussion Starter #168
Looking at the voltages I'm surprised the controller works at all. For the very low switch signal lines pullup voltage when the Y connector is plugged in the controller is never going to see the correct switch open/closed status. I would do a couple of thing for this based on the voltages you measured.
With the controller powered down and the Y connector connected measure resistance from the common 12V pullup voltage side of the resistors to ground, use any of the resistor ends with the 12V label or collector of the 751 transistor and measure from there to ground. Want to see what the load is the ZTX 751transistor is having to drive. If the resistance value seems reasonable then the second thing I would suggest doing is replacing this ZTX751 transistor. Seeing the same voltage on the base and collector of the 751 transistor makes me think there's a problem with the transistor.

The 2950A CZ5.0 voltage regulator output doesn't look good either, would expect this to be 5V. For this I would also check the resistance to ground from the output pin and if reasonable then replace the voltage regulator. The dark area around this device from high heat makes this device suspect or a high load from a shorted device it powers.

Really need to have decent voltage levels for the switch open/closed lines and 5V from the regulator to get things in better shape.

It is good to hear there is some progress being made, such as bow attempting to raise although I'm not sure how anything works with the low pullup voltage and VR output. Any luck with opening the soft top, does the compartment cover open? The other devices you measured look like power transistors (LP357Z) and I'm not certain those voltage indicate a problem.
I soldered new ZTX751 as replacement and now with Y connector unplugged I have emitter 11.2V, base 11.2V, collector 11.2V, however when Y connector is plugged in then base and emitter is the same voltage, but collector is 1.5V, consistently “12V” row with Y connector plugged in is 1.5V and with Y connector unplugged 11.5V.

N52 powered down resistance for “12V” row with Y connector unplugged is 4.3 mega ohms to ground and with Y connector plugged in resistance is 50 ohms. I have measured also pin resistance to ground in row with labels, there are two values either 0.3ohms or 630 ohms with Y connector plugged in (except for Y23 pin which had resistance of 2300 ohms)

5V regulator input 11.1V, but output is still 0.02V. N52 powered down 5V regulator output resistance to ground is 149 kilo ohms. That is too much, but I can’t figure out the issue yet.

I measured small transistors around the ZTX751 and two of them have unexpected results. T011 upper leg 9.6V, left leg 0.11V, right leg 0.06V. T015 upper leg 11V, left leg 0.03V, right leg 0.06V. However T013 has “normal” readings upper leg 5.5V, left leg 5V, right leg 5.7V

Y27 seams to be ok now, ST down 0V, ST up 1.5V on pin with Y label.

ST compartment cover unfortunately does not open yet.
 

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Hi Ryan, the 1.5V you measured after replacing the 751 transistor is this with the top closed or open? For the resistance you measured I calculated it should be between 80 and 120 ohms depending on how many switches are closed so 50 ohms is a little lower than expected but not unreasonable the ZTX 751 transistor should be able to drive 50ohm load without the voltage pulling down so low. The 11V on the base would mean the control line that's supplies a ground path and a voltage drop across the biasing resistors is not enable. Need to understand what enables this control line, may have something to do with no 5V from the VR.

From the voltages you measured yesterday I did see something that explains why you see so many error codes when the top is open as compared to when it's closed and why nothing happens when you're trying to close the top.

The 12V pullup voltage is 1.45V when the top is close and 0.13V when the top is open from your measurements. I noticed whenever a switch is open there was 1.45V on both ends of the resistor so no voltage drop but when the top is open there's 0.13V on one end and 0.25V on the other end of the resistor when the switch is open. The reason there is a small voltage drop is the OKI device has internal pullups and when the 12V pullup voltage is 0.13V the diode between the OKI device and switch signal line forward biases and you see the small voltage drop. When the top is closed and pullup voltage is 1.45V the diode doesn't forward bias so no voltage drop, which is correct and expected. This means the controller is probably seeing the correct switch open/closed status even when the pullup voltage is 1.45V (surprising but I think this is correct) but when pullup voltage is 0.13V and the OKI pullups are pulled low and the controller sees all switches as closed so this would explain all the error codes and no operation when top is open and you're trying to close it.

What doesn't make sense is why the pullup voltage is low and why is it even lower when the top is open. When the top is open there are even fewer switches closed so the load on the transistor is less (higher resistance, less current). Need to determine why base enable signal may not be happening and why VR not outputting 5V.

Here's what I think is happening when pullup voltage is 0.13V (top open).
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Discussion Starter #170
Hi Swany! Voltage measurements after soldering new ZTX751 were done with ST closed. I did measurements today with ST open, but that was before replacing ZTX751 and then voltage on labeled pins was 0.15V and resistance in "12V" row was 70 ohms. I don't think that ZTX751 had any influence on resistance on pins, so we can conclude that ST open there is 70 ohms resistance and ST close 50 ohms. That perhaps could also explain voltage differences with ST up and ST down, what do you think?

I think you are right with your theory, that when ST is open voltage is just not enough for N52 to see correct switch open/closed status.

If I understand correctly then there should be a minimum of 0.7V difference between base and emitter, so something should draw voltage from the base in order to turn on transistor, correct?
 

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Hi Swany! Voltage measurements after soldering new ZTX751 were done with ST closed. I did measurements today with ST open, but that was before replacing ZTX751 and then voltage on labeled pins was 0.15V and resistance in "12V" row was 70 ohms. I don't think that ZTX751 had any influence on resistance on pins, so we can conclude that ST open there is 70 ohms resistance and ST close 50 ohms. That perhaps could also explain voltage differences with ST up and ST down, what do you think?

I think you are right with your theory, that when ST is open voltage is just not enough for N52 to see correct switch open/closed status.

If I understand correctly then there should be a minimum of 0.7V difference between base and emitter, so something should draw voltage from the base in order to turn on transistor, correct?
The difference in resistance that you're measuring when top is closed and opened is the number of switches that are closed. Fewer switches are closed when the top is open so you have fewer resistors in parallel going to ground and a higher resistance overall. The resistance difference make sense but not the voltage difference, I would expected to be the other way around but overall the 12V pullup voltage is just not right because I don't think the 751 is being turned on correctly.

I'm having problems tracing the circuit around the 751 and 3 smaller transistors, if you could take a couple of photos of both sides of the board in this area it would be helpful.

For the PnP ZTX751 to turn on the base needs to be at least 0.7V lower than the emitter and it looks like this would happened if T011 was on but the base of this NPN transistor is at 0.11V. This is where I'm stuck, from the photos I can't determine where the traces go between the little transistor s (T011, T013, T015) and biasing resistors.
 

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I noticed whenever a switch is open there was 1.45V on both ends of the resistor so no voltage drop but when the top is open there's 0.13V on one end and 0.25V on the other end of the resistor when the switch is open.
In general I have not been following this thread closely enough to provide input, but I can follow the schematic that was posted.

The voltage drop across the resistor indicates there is current flowing into the collector of the PNP transistor (ZXT 751). As you know that's a problem for two reasons: (1) current can not flow into the collector of a properly-functioning PNP transistor, and (2) some part of the collector current most flow out of the base, and yet the voltage on the base indicates no current is flowing out.

Is it possible the circuit is different from what is depicted?
 

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Discussion Starter #173
The difference in resistance that you're measuring when top is closed and opened is the number of switches that are closed. Fewer switches are closed when the top is open so you have fewer resistors in parallel going to ground and a higher resistance overall. The resistance difference make sense but not the voltage difference, I would expected to be the other way around but overall the 12V pullup voltage is just not right because I don't think the 751 is being turned on correctly.

I'm having problems tracing the circuit around the 751 and 3 smaller transistors, if you could take a couple of photos of both sides of the board in this area it would be helpful.

For the PnP ZTX751 to turn on the base needs to be at least 0.7V lower than the emitter and it looks like this would happened if T011 was on but the base of this NPN transistor is at 0.11V. This is where I'm stuck, from the photos I can't determine where the traces go between the little transistor s (T011, T013, T015) and biasing resistors.
Swany here are the close up pictures of that area. Bob, considering what you are saying perhaps that is not full diagram of actual circuit, but I don't have such deep knowledge as you and Swany.

Back of chip side.jpg Chip side.jpg
 

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I have not been following closely enough to provide input, but I can follow the schematic that was posted.

The voltage drop across the resistor indicates there is current flowing into the collector of the PNP transistor (ZXT 751). As you know that's a problem for two reasons: (1) current can not flow into the collector of a properly-functioning PNP transistor, and (2) some part of the collector current most flow out of the base, and yet the voltage on the base indicates no current is flowing out.

Is it possible the circuit is different from what is depicted?
Hi Bob and yes, very possible circuit is actually different than depicted or incomplete, I can't follow all the traces from the photo. I'm not showing all the switch pullup resistors connected to the collector of the transistor, there's a resistor for every switch and all resistors are connected to the 12V pullup from the collector. The current path is likely back through one of the resistors where the switch is closed.
 

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In general I have not been following this thread closely enough to provide input, but I can follow the schematic that was posted.

The voltage drop across the resistor indicates there is current flowing into the collector of the PNP transistor (ZXT 751). As you know that's a problem for two reasons: (1) current can not flow into the collector of a properly-functioning PNP transistor, and (2) some part of the collector current most flow out of the base, and yet the voltage on the base indicates no current is flowing out.

Is it possible the circuit is different from what is depicted?
Here's 3 of the switch lines included. I'm showing one switch closed and a current path because of the very low pullup voltage present.

2612649
 

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Discussion Starter #177
Hi Bob and yes, very possible circuit is actually different than depicted or incomplete, I can't follow all the traces from the photo. I'm not showing all the switch pullup resistors connected to the collector of the transistor, there's a resistor for every switch and all resistors are connected to the 12V pullup from the collector. The current path is likely back through one of the resistors where the switch is closed.
Swany I made two better pictures so it is easier to see traces. It is difficult to see components, but traces are excellent.

PCB chip side.jpg PCB back side.jpg
 

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Swany I made two better pictures so it is easier to see traces. It is difficult to see components, but traces are excellent.

View attachment 2612652 View attachment 2612653
Thanks for the better pictures. If you can I would be interested in voltage measurement at these 3 points. Need to understand why base of T011 isn't at a higher voltage to turn it on, which would turn on the ZTX751.

2612654
 

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Ryan, you measured 0.11V on the base of the NPN T011 transistor and this voltage levels needs to be at least 0.7V to turn on TO11, which drives the base of the ZTX751 transistor low and turns it on, which supplies the 12V pullup voltage level. Because the measured voltage at the base of T011 is low this is a problem.

Here in the photo is what I think the voltages should be so please measure the key points to determine what the actual voltages are and from there we see what's going on. The problem may be the 5V supply voltage or the path to the microcontroller being low and dropping all the 5V across the one resistor. I don't know if the microcontroller is supposed to control the biasing of the T011 transistor or not but if this line is low it will prevent T011 and ZTX751 from turning on and why the 12V pullup voltage isn't there. It seems to me these transistors should be on when the controller is powered up or at the very least when soft top or rollbar switches are being pressed. You may want to measure voltages with the s84 power soft top button pressed to open or close too.

2612657
 

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Discussion Starter #180
Ryan, you measured 0.11V on the base of the NPN T011 transistor and this voltage levels needs to be at least 0.7V to turn on TO11, which drives the base of the ZTX751 transistor low and turns it on, which supplies the 12V pullup voltage level. Because the measured voltage at the base of T011 is low this is a problem.

Here in the photo is what I think the voltages should be so please measure the key points to determine what the actual voltages are and from there we see what's going on. The problem may be the 5V supply voltage or the path to the microcontroller being low and dropping all the 5V across the one resistor. I don't know if the microcontroller is supposed to control the biasing of the T011 transistor or not but if this line is low it will prevent T011 and ZTX751 from turning on and why the 12V pullup voltage isn't there. It seems to me these transistors should be on when the controller is powered up or at the very least when soft top or rollbar switches are being pressed. You may want to measure voltages with the s84 power soft top button pressed to open or close too.

View attachment 2612657
Hi Swany! I took the measurements and results are not what you expected, except one. Results were taken in normal state, nothing pressed, those are in yellow color and when S84 is pressed in red color.

I ordered 2950A CZ 5.0, it should arrive in two days, then I can replace that.
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