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I don't think that could be anything but the diagnostic socket.
 

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Discussion Starter #102
Hi Swany and Bob,

Bob you are right, that was diagnostic socket, so on older models it might be located in bottom right corner of passenger-side footrest. If any one wants to see it, check post No100.

I got interesting readings when RST module was in diagnostic mode. Soft top raised and locked, windows up, roll bar up I got one flash, so no errors. When soft top was lowered and in compartment, windows down, roll bar down I got following errors: 2,3,4,5,7,12,20. Error code meaning is the same as when RST module is in normal mode?

Immediately after reading these errors I disconnected Y connector and read switch positions what are on Y connector. Soft top lowered and in compartment, windows down, roll bar down switch positions: open 16,17,18,19,23,24,28,30; closed 10,20,21,22,25,26,27,29,31.

I understand that errors are conflicting with reading on Y connector, correct?
 

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Hi Swany and Bob,

Bob you are right, that was diagnostic socket, so on older models it might be located in bottom right corner of passenger-side footrest. If any one wants to see it, check post No100.

I got interesting readings when RST module was in diagnostic mode. Soft top raised and locked, windows up, roll bar up I got one flash, so no errors. When soft top was lowered and in compartment, windows down, roll bar down I got following errors: 2,3,4,5,7,12,20. Error code meaning is the same as when RST module is in normal mode?

Immediately after reading these errors I disconnected Y connector and read switch positions what are on Y connector. Soft top lowered and in compartment, windows down, roll bar down switch positions: open 16,17,18,19,23,24,28,30; closed 10,20,21,22,25,26,27,29,31.

I understand that errors are conflicting with reading on Y connector, correct?
There's no correlation between all the errors codes and the limit switches results. Still looks like controller problems, it's not a limit switch or two having a problem, too many errors and switch results look good to me. Interesting thing everything looks okay when the top is closed yet so many errors when open. Do you still have the jumpered wired on FX2.10?

Would it be possible to get a better photo of the top and bottom side of the relay board. I'm still trying to trace the circuits causing the S84 switch problem. I did notice there is some feedback to the controller board from the S84 circuit that turns on the relay coil so if not working as expected the levels feedback from the circuit would cause other issues than just the hydraulic pump not running.

You mentioned you checked the two transistors; can you tell my how your checked them out and the results of your measurements. Levels on E,B,C when switch is pressed and when not. It will help with debug.

Need a better photo of this area, basically as high res as you can do and the entire top side of the board. Bottom too if you can manage. Thanks
2610989
 

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Discussion Starter #104 (Edited)
There's no correlation between all the errors codes and the limit switches results. Still looks like controller problems, it's not a limit switch or two having a problem, too many errors and switch results look good to me. Interesting thing everything looks okay when the top is closed yet so many errors when open. Do you still have the jumpered wired on FX2.10?

Would it be possible to get a better photo of the top and bottom side of the relay board. I'm still trying to trace the circuits causing the S84 switch problem. I did notice there is some feedback to the controller board from the S84 circuit that turns on the relay coil so if not working as expected the levels feedback from the circuit would cause other issues than just the hydraulic pump not running.

You mentioned you checked the two transistors; can you tell my how your checked them out and the results of your measurements. Levels on E,B,C when switch is pressed and when not. It will help with debug.

Need a better photo of this area, basically as high res as you can do and the entire top side of the board. Bottom too if you can manage. Thanks
Yes that was interesting for me, that when ST is up, then no errors, when ST down so many errors. Switches seems to be ok, so it should be controller problem. I'm thing perhaps they have some common circuit in N52 module?

No, I don't have wire jumpered FX2.10 any more, but I can solder it back at any time.

Two transistors I soldered out and tested base to collector (like diode), base to emitter (like diode), collector/emitter open circuit. I did not test them module connected to car. If that will help I can try to measure when module is connected to car.

I'm attaching pictures from module in best resolution I can. I made two pictures for each side.

Relay back side 1
2611024


Relay back side 2
2611025


Relay side 1
2611028


Relay side 2
2611029


Chip side 1
2611030


Chip side 2
2611031


Chip side back 1
2611032


Chip side back 2
2611033
 

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Board photos are very good. Thanks, this will help me trace things better. I ran into a few dead ends before so these new photos will hopefully enable me to find the connection between the roll bar and power soft top switches circuits.
 

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When soft top was lowered and in compartment, windows down, roll bar down I got following errors: 2,3,4,5,7,12,20. Error code meaning is the same as when RST module is in normal mode?
Yes, the codes as for the under-hood diagnostic socket.

The microcontroller is reading all four switches associated with the compartment cover as closed all the time. Without a copy of the program running on the microcontroller or other documentation this problem may be prohibitively difficult to solve.

I would pick one of those switch inputs and follow it as far as necessary to determine why it is always being read incorrectly. I wouldn't concern myself with the relay 18 circuits.

The relay is operating perfectly fine with the jumper in place. The consequence of the jumper is that you have bypassed a nonessential element which prevents the pump from running continuously in the case of transistor failure. That bypass is entirely moot if you can not get the roof to operate.
 

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Discussion Starter #107 (Edited)
Yes, the codes as for the under-hood diagnostic socket.

The microcontroller is reading all four switches associated with the compartment cover as closed all the time. Without a copy of the program running on the microcontroller or other documentation this problem may be prohibitively difficult to solve.

I would pick one of those switch inputs and follow it as far as necessary to determine why it is always being read incorrectly. I wouldn't concern myself with the relay 18 circuits.

The relay is operating perfectly fine with the jumper in place. The consequence of the jumper is that you have bypassed a nonessential element which prevents the pump from running continuously in the case of transistor failure. That bypass is entirely moot if you can not get the roof to operate.
Is there any other common circuit for all four switches associated with the compartment cover before microcontroller? For example Oki chips? SA5090D communicates microcontroller to relays, correct? So that would be already after microcontroller? Do you know can OKI chips be easily replaced, they are not programmed are they?
 

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I don't know anything about the circuits involving the limit switch inputs other than that the OKI chips are used to interface them with the microcontroller. The OKIs require no programming.

The Signetics SA5090Ds multiplex the microcontroller outputs to the various relays.
 

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Discussion Starter #109
I don't know anything about the circuits involving the limit switch inputs other than that the OKI chips are used to interface them with the microcontroller. The OKIs require no programming.

The Signetics SA5090Ds multiplex the microcontroller outputs to the various relays.
Thank you Bob! Just ordered two OKI chips, really hope that they will be faulty, but not the microcontroller. To fix this module after all this time would give me a lot of satisfaction. Well either way in this thread there is a lot of useful information, pictures, tables and schemes for anyone who will attempt to fix N52 module. Thank you very much Bob and Swany you are great guys and knowledgeable experts! I'm not giving up yet :)
 
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