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Discussion Starter #221
Here are some of the voltages you should expect to bias the T011 and T012 transistors based on the 5.68V supply voltage you've measured. With the resistor modification you should see ~1.9V on the base of the T011 transistor and ~11.2V on the collector of the T012 when it's turned on.

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I soldered resistors in the configuration as in your picture. But no changes to pullup voltages, T012 collector 1.5V. The only value that matches expectations is the voltage on right resistor lower leg which is 5.68V as it was before. Voltage in corner where resistors are joined together is 0.65V and base of the T011 is 0.11V as before. Microcontroller Pin31 is 0.65V. Roof operation as before from ST raised and locked position it gets to the point when both bow locks unlatches and bow pops out. At this point voltage on T012 collector is 0.56V. No wonder nothing happens further.
 

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Hi Ryan, I screwed up and I don't know why I didn't see this before but what I had you do is not going to work because the line to the microcontroller is still not bypassed. The top right pad is still connected to the line going to pin 31 of the microcontroller. You can do one of two things to correct my mistake. Resolder the two resistor in a position so they do not connect to the top right pad where they join. Make like a V bridge with the resistors and don't solder the joined resistors to the top right pad, have it raised above the board with no contact to the pad. The right corner where they're joined would be up off the board while the two ends of the joined resistors are soldered as they are now. Or, cut the trace to the pin 31. Sorry about this. Let me know if this doesn't make sense. Please try again, I'd really like to know what happens with the top operation when you get the 12V pullup voltage back for the switches. Assuming there's no other problems you should see good progress with the top operation and there's a solution if the one line, pin 31, is the only problem.

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Discussion Starter #223
Hi Swany! OK, no problem, good that it didn't short out anything. So the last resistor set up worked. Got 11V on ZTX751 collector, so that means for all 12V pull up row. But got lower value on T011 base then expected only 0.7V and upper leg 0.098V, left leg 0.07. Microcontroller Pin31 0.8V and Pin35 5.68V.

There are improvements in roof operation. From raised and locked roof, basically the same story, bow unlocks, pops out and then stops and it seams that only one side is going up, if try to close then vice versa. However when ST is open and N52 in diagnostic mode, there are no errors anymore. From that position ST compartment cover opens fully, St rises half way and I think it would go further, but battery run out of juice. Left it to charge.

Thank you very much, you have very good ideas and solutions!

So there are improvements, but since we are bypassing microcontroller, does that means microcontroller is bad, pin31 is damaged? Do you know what for it was originally intended?
 

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Hi Swany! OK, no problem, good that it didn't short out anything. So the last resistor set up worked. Got 11V on ZTX751 collector, so that means for all 12V pull up row. But got lower value on T011 base then expected only 0.7V and upper leg 0.098V, left leg 0.07. Microcontroller Pin31 0.8V and Pin35 5.68V.

There are improvements in roof operation. From raised and locked roof, basically the same story, bow unlocks, pops out and then stops and it seams that only one side is going up, if try to close then vice versa. However when ST is open and N52 in diagnostic mode, there are no errors anymore. From that position ST compartment cover opens fully, St rises half way and I think it would go further, but battery run out of juice. Left it to charge.

Thank you very much, you have very good ideas and solutions!

So there are improvements, but since we are bypassing microcontroller, does that means microcontroller is bad, pin31 is damaged? Do you know what for it was originally intended?
This is good progress and good news about the health of the control module. No errors in diagnostic mode is real progress and means some of the remaining problems you're having with the top operation is not due to the control module.

Pin 31 may be damaged and this assumes there's no hidden path under the Intel chip for this pin. Another path would possibly indicate a problem somewhere else. Even if this pin is damaged and unusable I think there might be a workaround. If I'm correct about how the controller works pin 31 only comes into play when the car is moving and the speed signal is active. From all the measurements you've done it looks like the speed signal is used to set the logic level on the EA pin, pin 35. When the speed signal is active as the car moves the EA signal goes to a low ligic level (from comparator A LM2093 chip). From what I've read about the Intel microcontrolller when the EA signal is low it fetches its program code from external memory and there's a separate EEPROM chip that contains the external memory.

When the car moves I think the RST module changes mode because of the different program code it's using from external memory. This make sense because you don't want the normal top open/close operation enabled when the car is in motion. I was also trying to understand why the Intel controller controlled the 12V pullup voltage to the switches, this is what pin 31 does. With pin 31 bypassed your top operation should work to open and close the top okay when the car isn't moving, however, with pin 31 bypassed you may get an error code when the cars is moving.

Here's why I think pin 31 is used to disable the 12V pullup voltage. When the car is in motion and the speed signal is present the EA signal goes low and I think this is time when pin 31 should also go low to disable the pullup voltage. When the 12V pullup voltage is missing all the switches are read as closed/low except one switch that has it's own 12V pullup voltage. I think the status of the switches is this unique configuration is for the microcontroller to read and know the car is now in motion and to disable opening or closing the top. If I'm correct about all this you may see some problems when you start driving the car, like error codes. I would leave things the way they are right now and continue to work on the remaining top operation problems. If pin31 is the only remaining issue with the RST module then I think there's a way to connect the biasing resistors to another place other than pin 31 and restore an equivalent low signal at the correct time. When you get the car moving we'll have to see what happens and I'll need you to monitor pin 31 and pin 35 to see what these pins do when the wheels start spinning.

Nice work, you've repaired a lot problems so far, transistors, diodes, caps and a voltage regulator and now no errors. Please keep us updated how things go going forward. I'm optimistic you can get the RST module completely functional now.
 

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Discussion Starter #225
Thank you both Swany and Bob, especially you Swany. I learned a lot during this process. I hope this thread will be helpful to anyone who will attempt to fix N52 himself. I think we have covered most of the module. I will definitely keep you updated during the renovation process and once I will get to fixing the remaining issues with ST.
 

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Thank you both Swany and Bob, especially you Swany. I learned a lot during this process. I hope this thread will be helpful to anyone who will attempt to fix N52 himself. I think we have covered most of the module. I will definitely keep you updated during the renovation process and once I will get to fixing the remaining issues with ST.
Thanks to you too for all the work you've done measuring voltages and tracing the circuit connections. I'll go through all my notes and circuit drawings to update and post everything when things are cleaned up. We did cover a lot of the module tracking down multiple problems. With so many component failures this module looks like it got hit with an voltage spike, maybe from a jump start. Hopefully Bob can review what I'll post later and compare with his notes and correct any errors. I don't know how much of a schematic exists for this module but I did try to capture as much as I could from your photos and tracking down connections.

Still need to understand how the module works when the car starts moving. From what it looks like, and this is where I could really use Bob's help, it looks like there's two different speed signals one from the speedometer and one from the wheel. The speedometer speed signal is an input to comparator A of the LM2903 device and the output goes to the EA pin of the microcontroller and pin7 port 1.5 connection. The wheel speed signal goes to the base of a small transistor (T016) that has the collector connected to a second resistor of the comparator A output and I'm not sure how all this works together.

Anyway, would like to hear how things go with the remaining top operation problems.
 

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Discussion Starter #227
Yes, I would too appreciate Bob opinion on the last problem we had and the solution/temporary solution we made. Perhaps he has something interesting ideas or had faced similar issues in the past.
 

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Ryan, when you get a chance can you take some more pictures of the the area shown, both sides of the board. I'm trying to figure out how the T016 transistor is connected and where the power supply for the 93C46B comes from. The backlighted photos are great. The photos I have don't show to the edge of board. thanks

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Discussion Starter #229
Swany I will take more pictures during the weekend. The latest update is that it seams that N52 is functioning now. I don't have any errors in diagnostic mode, neither when ST is open, nor when it is closed. When ST is open and closing it with S84, ST compartment cover opens and ST rises to vertical position, but it can get bow out of compartment. When ST is closed, then bow locks unlatch and bow pops out, but does not rise. I don't get any errors in N52. It seams the issue is either mechanical or hydraulic. Since ST is easy to open and close manually, however when ST is operated with S84 I see that both main cylinders and left compartment lock cylinder is leaking, I think the problem is hydraulic system or pressure. Too bad I can't upload video here. I will go through hydraulic ultimate tread in this forum and search some more threads in this forum.
 

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Thanks for taking the additional pictures when you can and thanks for the update. Does the bow still look like one side is working against the other side? Could it be possible the hydraulics lines to the one bow cylinder is crossed either at the bow cylinder or at the valve block? Don't think this is a N52 problem.

I've been trying to understand the circuit that has something to do with pin 31 of the microcontroller and I think I understand it now. It has to do with the vehicle speed signals and based on whether the speed signals are present or not it changes the microcontroller program fetched so the N52 changes it's overall mode of operation when the car is in motion vs when it's stationary. Is your car driveable? If so it would be interesting for you to drive the car some and see how the N52 module does. Will it generate any error codes because the pin 31 signal is missing.

The circuit shown below shows the instrument cluster and wheel speeds signal inputs and the output that changes the programming of the microcontroller is the EA pin 35 signal. This circuit also checks for missing instrument or wheel speed signals so there are other signals that go back to the microcontroller. The only way to check the other mode of operation for the N52 module is to drive the car so both the instrument and wheel signals are present and why I asked if the car is driveable. If there is a problem then you may need to add some wires to pin31 and pin 35 and bring them out of the module so you can see what the voltage levels are for these signals when the car moves. You're going to need a helper if this is the case.
If necessary I do think the pin 31 signal can be replaced by adding a wire to the base of the transistor that used to be controlled by pin 31 of the microcontroller and routing the wire to another location where it can be pulled low when EA is low, which is when the car is in motion but this needs to be verified. Overall the N52 module sounds like it good shape now and maybe one more item to take of for full operation in addition to the bow hydraulics issue.
 

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Discussion Starter #231
Hi Swany! I have attached backlighted pictures of the area you wanted. If you need anything more, any picture or measurement just let me know.

The car is not drivable yet, so unfortunately I can't take measurements when the car is driving.

I have many leaking cylinders, it looks like that almost all that have been in action so far, except both bow lock cylinders. At the moment it looks like that left side of bow is rising but right is not, this is based on the observation when opening the ST from closed position and closing ST from open position.

I'm planing to repair all cylinders, so there is no hydraulic leaks and then see what is going on. Perhaps I should test the full "chain" for right bow: valve, wiring, hydraulic fluid flow.

Regarding vehicle speed signal and why N52 wasn't working, I'm thinking that maybe Pin31 wasn't damaged. We didn't test vehicle speed signal input, perhaps the problem was in this input or that N52 thought it was missing.

Backlighted 1.jpg Backlighted 2.jpg
 

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Hi Swany! I have attached backlighted pictures of the area you wanted. If you need anything more, any picture or measurement just let me know.

The car is not drivable yet, so unfortunately I can't take measurements when the car is driving.

I have many leaking cylinders, it looks like that almost all that have been in action so far, except both bow lock cylinders. At the moment it looks like that left side of bow is rising but right is not, this is based on the observation when opening the ST from closed position and closing ST from open position.

I'm planing to repair all cylinders, so there is no hydraulic leaks and then see what is going on. Perhaps I should test the full "chain" for right bow: valve, wiring, hydraulic fluid flow.

Regarding vehicle speed signal and why N52 wasn't working, I'm thinking that maybe Pin31 wasn't damaged. We didn't test vehicle speed signal input, perhaps the problem was in this input or that N52 thought it was missing.

View attachment 2614193 View attachment 2614194
Thanks for the pictures, these will help.

Here are my notes from when I removed, rebuilt and replace all my top cylinders. You're model year will be different in some ways but very similar. Removal of bow cylinders will be the biggest difference.

Is it possible to help the bow up manually while opening the top automatically to see if all sequences will complete.

 

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Discussion Starter #233
Thank you Swany! Your notes are very helpful, in great detail and very informative.

Helping ST manually with hands does not make any difference in my situation in those positions ST gets stuck.
 

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What's the current symptoms with the ST opening and closing? When closing the top where does it stop and when opening where does it stop? When you tried to assist raising the bow manually while operating the top with the switch where you able to raise the bow enough to activate the bow switch? I'm trying to determine if the bow is being raised high enough to close the left bow "raised" switch.
 

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Discussion Starter #235
What's the current symptoms with the ST opening and closing? When closing the top where does it stop and when opening where does it stop? When you tried to assist raising the bow manually while operating the top with the switch where you able to raise the bow enough to activate the bow switch? I'm trying to determine if the bow is being raised high enough to close the left bow "raised" switch.
I will take some pictures so you get better understanding of the ST operation. When opening ST, then bow locks unlock, bow pops out and left side of bow raises several inches, but right side stays doesn't. Front locks do not unlock. That is it, no further then that.

When closing ST, then ST compartment cover opens, ST rises to almost vertical position and it seams that it does not have enough power, but bow does not come out from ST compartment, again left side of bow raises several inch, but right is completely down in ST compartment. Then it all gets stuck.
 

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Yes, pictures or video would help. One question for now though, if you turn the ignition off when the top is stalled out in the opening or closing sequence can you move the bow manually to the fully raised position? Does it seem like a mechanical movement type problem of a hydraulic problem?
 

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Any updates?

Also, Swany, when this thread is concluded do you suppose you might have a partial schematic of the controller to share with us?
 

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For drawing schematics you may be interested in PSPICE. It's primarily used to simulate electronic circuits but it is also very good for drawing schematics. There are "student" versions which are free to download and use. Here's one: Electronics-Lab.
 

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For drawing schematics you may be interested in PSPICE. It's primarily used to simulate electronic circuits but it is also very good for drawing schematics. There are "student" versions which are free to download and use. Here's one: Electronics-Lab.
I'll give PSPICE a try. For now I'm going to post pdf format what I've drawn in Visio. I'm going to post in sections with photos and measurements from Ryan. The schematics and notes may be incorrect in many ways so please review and I'll make any corrections needed. If I had non-repairable (junk) circuit boards I could remove the components and complete the schematics since there are dead ends when the traces go under the components and can't follow anymore. I've attached the circuits related 12V pullup voltage to switches, signals from instrument and wheel speed signals to comparators and control signals to and from the microcontroller. I have some more schematics on other sections I'll post later.



Ryan can give the lastest update on some of the remaining problems with his top operations.
 
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