Garmin GSC 10 speed not working
jpower
Posts: 554
Picked up a GSC 10 second hand, all looks ok, the candence is working, however the speed is not reading, I noticed in some videos of fittings the magnet has a line in it, mine does not, does that mean I need to keep moving the magnet to try and find this line? Or should it work so long as the arm and magnet and aligned?
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both magnets must be aligned with their respective indication lines for the Edge to receive the data. As your hasn't got the line, I would suggest assume the line runs through the middle.
Your best bet would be to go to Garmin's website and download the manual0 -
I did look at the manual: http://static.garmincdn.com/pumac/Speed ... ngual_.pdf
But poor detail on speed magnet, but glad you said there should be a line, thats probably the reason, once it stops raining will go out and mess around a bit more.0 -
If you look at the sensor, you'll see that there are two small grooves on it - one for the centre of the speed sensor on the "torpedo" on the arm, and one on the main body for the centre of the cadence sensor. Line the relevant magnets up with, and within 5mm gap to these marks. And the sensor has a blinking light on it to show if it's picking up the magnets - the small white soft button. Press it in for a few seconds to "reset", then as the magnet passes the sensor you should see it flash green (I think!). It's very faint, and I do mine in an unlit - so fairly dark - shed to make it easier to see. It'll only flash for the first 10 passes of the magnet after resetting though, after that it goes off and you need to reset again if you need more visual indication. I usually need to try a couple of times each for the wheel (speed) and crank (cadence) sensors.0
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So I see the faint line on the torpedo, very close to the back, tried messing around with the magnet, no joy, here a picture, does this look right?
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If you have a bike stand I put mine up on that, and rest the gsc 10 and you can see the button flash red/green when the magnet goes through and I kept messing around with it until both flashed than it worked ok, the manual on the Garmin website is really good0
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Doing in a stand, reset flicks red and green, then crank arm flicks red on rotation but never any green. Starting to think speed part is faulty. Is manual you mention the same as my link above?0
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jpower wrote:Doing in a stand, reset flicks red and green, then crank arm flicks red on rotation but never any green. Starting to think speed part is faulty. Is manual you mention the same as my link above?
Red flash with crank arm means cadence ok. You need to just use the rear wheel and look for red when magnet passes to show speed ok. And maybe try and get the magnet closer - you can swing the torpedo arm upwards for more adjustment..0 -
You mean green light for speed right?rafletcher wrote:jpower wrote:Doing in a stand, reset flicks red and green, then crank arm flicks red on rotation but never any green. Starting to think speed part is faulty. Is manual you mention the same as my link above?
Red flash with crank arm means cadence ok. You need to just use the rear wheel and look for red when magnet passes to show speed ok. And maybe try and get the magnet closer - you can swing the torpedo arm upwards for more adjustment..
Can one of the systems not work while the other does, really don't think its me, thinking it's the unit.0 -
Quite common, apparently - the reed in the speed sensor stops working or only intermittently, while the cadence sensor is fine. The speed sensor reed seems too delicate. If under warranty then Garmin seem very good at replacing them but as its second hand that could be more of a worry...0
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Garmin also replace 2nd hand under warranty if you can vouch for who the original seller is.
I got a replacement edge for £65 for one bought from the classifieds here, as I had the seller's details. They kindly reregistered it in my name as well.0 -
i noticed at the weekend that my sensor was not functioning correctly and i initially thought it was the battery that had to be replaced. It turned out that the unit was slightly tilted and as a result the whole damn thing stopped working!0
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On mine, my speed sensor stopped working although my cadence was still working. I replaced the battery and now all okay. As you bought second-hand maybe worth just changing the battery and see if that works.0
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Tried that, think I need to concede that the speed part is broken.ForumNewbie wrote:On mine, my speed sensor stopped working although my cadence was still working. I replaced the battery and now all okay. As you bought second-hand maybe worth just changing the battery and see if that works.
Question: The average speed I take it that gets calculated via combination of time and distance, so all I am really losing is accurate current speed and maybe a litter error in distance covered, is my understanding correct?0 -
Try taking the battery out and fitting it the wrong way round for a few seconds. This resets the unit. Also worth giving the speed pick up a sharp tap (flick it with your finger). The reed switch sometimes sticks if not used for a while.
Speed is worked out from time and distance. On twisty or hilly roads the GSC10 distance reading is usually better than the GPS one, but not by a lot.0 -
Ha ha, done the above now the cadence stopped readingJohn.T wrote:Try taking the battery out and fitting it the wrong way round for a few seconds. This resets the unit. Also worth giving the speed pick up a sharp tap (flick it with your finger). The reed switch sometimes sticks if not used for a while.
Speed is worked out from time and distance. On twisty or hilly roads the GSC10 distance reading is usually better than the GPS one, but not by a lot.
Might just call it a day on this one.0 -
you may have to re-pair the device with your garmin to get the cadence working once more.
It sounds like you have a dodgy connection or switch with the speed sensor part though .
I usually test these devices by using a spare magnet to wipe past the suspect unit rather than rely on placing the magnet correctly on the wheel/crank.0 -
good idea, will try this, but bike now gone to another location in prep for palace to palace ride on Sunday, so won't be doing any tinkering till Sat.Slowbike wrote:you may have to re-pair the device with your garmin to get the cadence working once more.
It sounds like you have a dodgy connection or switch with the speed sensor part though .
I usually test these devices by using a spare magnet to wipe past the suspect unit rather than rely on placing the magnet correctly on the wheel/crank.0 -
jpower, if I was you I would remove the GSC10 from the bike altogether for your big ride so that your speed and distance will calculate correctly from the GPS. You will not have cadence measured, but I would sacrifice that for accurate speed and distance.jpower wrote:
good idea, will try this, but bike now gone to another location in prep for palace to palace ride on Sunday, so won't be doing any tinkering till Sat.Slowbike wrote:you may have to re-pair the device with your garmin to get the cadence working once more.
It sounds like you have a dodgy connection or switch with the speed sensor part though .
I usually test these devices by using a spare magnet to wipe past the suspect unit rather than rely on placing the magnet correctly on the wheel/crank.0 -
No need to remove the device - perhaps just the magnet from the wheel ...0
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Do Garmins display their speed and distance just from the GSC-10 or does it also use GPS to work out these out?
Does software like Strava use GPS to work out speed and times, rather than the GSC-10 data?
Do the Garmins use GPS to calibrate the GSC-10 as I was wondering if where you place the magnet and sensor has an effect on the speed? For example, If they were placed closer to the axle/hub would they under read compared to being placed closer to the rim?
On my Garmin, the settings showed - Wheel Size Automatic 2088mm. Which is confusing me as I'm sure 700c wheels have a diameter from tyre bead to bead of 622mm. The tyres fitted are 700-23C with a diameter of 23-622. Then next time I turned it on after scrolling through the menus the Garmin now shows Wheel Size Custom 2096mm."The Prince of Wales is now the King of France" - Calton Kirby0 -
You can set the wheel size manually, or set it to automatic, in which case it will calibrate over a distance based on GPS. The automatic/GPS calibration is as accurate as you can possibly get.
If you have a GSC-10 paired then apart from the calibration, it bases all speed and distance measurements on the speed sensor and only uses GPS for plotting the route to display on computer later.
However, some software may recalculate distance/speed from the GPS co-ordinates when you upload. This will not be as accurate as the GSC-10 though as there will be loss due to sampling rate and altitude change.0 -
As per usual I got fed up with this and put a new GSC 10 on and voila everything seems to work as expected. I'll know better tomorrow after the palace to palace ride.0
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Had the same problem. Cadence worked, speed just stopped working.
Here's what I did:
Un paired the sensor and the head unit (in my case a Wahoo Elemnt Bolt)
Pressed reset button
Removed battery
Inserted battery backwards (reverse polarity)
Removed battery
Reinserted battery In proper direction
RE-paired the devices
BINGO!0 -
I bet you 20p that it will go again... If its the reed that has gone then its normally intermittent for a while so you may think it is fixed but it probably isnt.0
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Happy to report 3 years on mine still working perfectly. Although we all know that I just jinxed myself. Damn.0
