Fore/Aft drivers seat Hall sensor fault/ Other electrical Issues

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Dec 6, 2021 | 04:28 PM
  #1  
Code B1200, Component M27m1 (fore/aft motor) Hall sensor fault. All other functions of the electronic seats work, just not moving forward or back. I am very poor with electrical issues on vehicles, so, is the hall sensor in the seat motor? If it is and I need to replace the motor, how can I get the seat out as it is all the way back and does not allow me to reach the bolts in the rail for removal.
Also, I have a historic code from the ECM: P1570 Fault in DAS to engine control module. I have not idea what this is!!! My other electrical issues are: 1) front window switches do not work, the rear window switches do work , but lower both the front and rear windows. 2)The soft top will not go down as the latch will not operate to release the rear of the top, and I cannot lower the roll bars. I can hear the switch click behind the seat but they will not lower. Any type of help with these issues is appreciated!!!
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Dec 13, 2021 | 06:54 AM
  #2  
Check all fuses in the boot fuse box, also the seat motors suffer from sticking brushes so I have cured a non moving seat just by giving the seat base cushion a good thumping.
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Dec 13, 2021 | 01:01 PM
  #3  
Thanks for the reply. I have checked all fuses and relays and they are OK. I have also tried to tap the motor and that did not work. I am not sure, but I believe that the seats, windows and rear head rests are on the same circuit. If that is the case it would make sense as the front window switches do not work and I cannot lower the rear headrests. To bad because mechanically the car runs great. I cannot get the front drivers seat out because it is stuck all the way back.
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Dec 14, 2021 | 03:21 AM
  #4  
Quote: Thanks for the reply. I have checked all fuses and relays and they are OK. I have also tried to tap the motor and that did not work. I am not sure, but I believe that the seats, windows and rear head rests are on the same circuit. If that is the case it would make sense as the front window switches do not work and I cannot lower the rear headrests. To bad because mechanically the car runs great. I cannot get the front drivers seat out because it is stuck all the way back.
I've attached a wiring diagram for seat and door control modules so if you can use a multi meter you can start checking supply voltage to each module. My seat operate without a key in the ignition so powered all the time. Be aware fuses can visually look ok but best to test them with a meter. Hope this helps.

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Dec 14, 2021 | 04:16 PM
  #5  
Thanks, I'll give it a shot
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