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My sunroof will only open 25% of the way and it has the wind deflector that comes out and then it stops then I can close it and it will vent but I cannot get it to open more than 25% is there anything I can do to correct this problem? I did also notice an issue where my sunroof did not operate at all and I was able to fix that by putting two relays in and bypassing the circuit board connected to my motor. Does anyone have a circuit board laying around from their sunroof motor they're not using they may want to part with and can send one to me? I am including a picture of the part I'm talking about that was connected with my motor.
I'm wondering if there's something I can do to fix the alignment or whatever it may be that's stopping the sunroof from opening more than 25% though maybe something got misaligned please let me know any help would really be appreciated. Thank you
You should recalibrate the sunroof first before going any further. Hold the tilt up switch for 10 seconds until the sunroof tilts up then down, then release the button.
There is an encoded motor that sends a signal back to the BCM, the BCM knows how many encoder pulses it should see to open but it's all based on how many encoder pulses it saw last time it closed.
For example, if you were opening the sunroof and it's supposed to take 50 encoder pulses to open but you interrupted power halfway through so it only saw 25 pulses, then when you closed the sunroof again it's only going to count 25 pulses and on the next opening it's going to only count open 25 pulses and thus leave the thing halfway open.
Normally encoder pulses are a learned-count method like the window motors, you run the window through it's full range as part of the recalibration and the BCM counts pulses then every time you auto up/down the window it uses that pulse count. The sunroof doesn't have that kind of operation though, you just "zero out" the motor and the BCM has a predetermined number of counts it's using to open. I think your zero setting is off though, thus why you need to recalibrate it to zero by holding that button.
If that doesn't fix the issue it's probably the motor itself that's failed and sending the wrong encoder pulse count to the BCM.
EDIT: I should specify that I don't know EXACTLY what's going on in the BCM just taking a guess based on how the recalibration steps work. It's possible that it's counting pulses on the tilt up/down and using that as a reference for pulse count to slide open. However it doesn't use a cable stop like the window motors so I think it's just a pulse count reset to zero.
Last edited by cleric670; Jun 7, 2021 at 03:51 PM.
You should recalibrate the sunroof first before going any further. Hold the tilt up switch for 10 seconds until the sunroof tilts up then down, then release the button.
There is an encoded motor that sends a signal back to the BCM, the BCM knows how many encoder pulses it should see to open but it's all based on how many encoder pulses it saw last time it closed.
For example, if you were opening the sunroof and it's supposed to take 50 encoder pulses to open but you interrupted power halfway through so it only saw 25 pulses, then when you closed the sunroof again it's only going to count 25 pulses and on the next opening it's going to only count open 25 pulses and thus leave the thing halfway open.
Normally encoder pulses are a learned-count method like the window motors, you run the window through it's full range as part of the recalibration and the BCM counts pulses then every time you auto up/down the window it uses that pulse count. The sunroof doesn't have that kind of operation though, you just "zero out" the motor and the BCM has a predetermined number of counts it's using to open. I think your zero setting is off though, thus why you need to recalibrate it to zero by holding that button.
If that doesn't fix the issue it's probably the motor itself that's failed and sending the wrong encoder pulse count to the BCM.
EDIT: I should specify that I don't know EXACTLY what's going on in the BCM just taking a guess based on how the recalibration steps work. It's possible that it's counting pulses on the tilt up/down and using that as a reference for pulse count to slide open. However it doesn't use a cable stop like the window motors so I think it's just a pulse count reset to zero.
I am unable to do this because that board that is connected to the motor will not work when I have it connected I can't do anything. I can apply power directly to the motor and it does work however it will only go so far when I'm opening the sunroof with it. What I did temporarily until I can get that board replaced is used to relays so I can use it with reverse polarity on that same motor.
