AXS shifting intermittent failure

[cookie70]

Hi everyone,

I got the GX upgrade kit recently and for the most part have been very happy with it. However, I've recently had a few times where shifting stops working while riding and having to pull the battery to get it running again. It seems to happen on really rough trails so I wonder if the battery is not connecting fully even though it has the latch locked.

any thoughts on this, its getting a bit annoying and I am thinking of going back to cables..

This one ride below, I could not get it shifting again. but it was fine once I got home and shut everything off

 

[RichT]

I’m planning an AXS upgrade so this is good info….watching

 

[cookie70]

another example where shifting went dead but came back after pulling battery

 

[Rod B.]

another example where shifting went dead but came back after pulling battery

View attachment 106673

Cookie,

Have you checked the contact prongs on the derailleur? It sounds like the battery is loosing electrical contact with the derailleur. The two prongs on the derailleur are supposed to move freely. If they are sticking or dirty this might be the cause. Check the prongs to see if they are sticking and not moving freely.. I would also buff the contact points with a piece of fine steel wool to clean them up.

It’s a shot in the dark, but worth trying.

Rod

 

[RustyIron]

where shifting stops working while riding and having to pull the battery to get it running again. It seems to happen on really rough trails

Disclaimer: I don't know, I'm guessing.

When I have a system that is behaving in an unexpected manner, the first thing I do is make sure I'm running the latest firmware. There have been a couple updates recently, so do that first. It's the easy thing to do, it's the logical thing to do, and it's one variable you can cross off the list.

 

[crazyethnic]

sounds like a warranty job your getting poor connection.

 

[cookie70]

Disclaimer: I don't know, I'm guessing.

When I have a system that is behaving in an unexpected manner, the first thing I do is make sure I'm running the latest firmware. There have been a couple updates recently, so do that first. It's the easy thing to do, it's the logical thing to do, and it's one variable you can cross off the list.

its all on the latest updates, first thing I tried

 

[cookie70]

sounds like a warranty job your getting poor connection.

yeah possibly, it was working fine up until about 2 weeks ago, then just this strange non-response. I feel like it happens when I get into super rough ground, maybe the thing thinks its been hit and disconnects??

 

[Mikerb]

Next time it stops working press the button on the mech rather than removing the battery . If the mech moves it proves the battery contact is ok. If it does not move then it is likely to be a poor battery connection and a good clean should fix it.

If the mech moves when pressing the button, then try the selector. If it does not work then the problem is possibly at the selector. If it does work then it suggests the mech has been hit or is stuck.....try cleaning the pivot points and spring.

 

[Mikerb]

One other potential cause is excessive chain slap running over rough ground in the highest gear......the mech clutch may not be totally effective if the mech is clogged with dirt or the chain may be too long.

Ps I would advise against using any abrasive to clean the battery contacts. That will destroy the contact surface layer which is either a precious metal or special coating. Just use contact cleaner and a soft brush...and wipe with a clean rag or tissue.

 

[Stoneilove]

I have the AXS 01x with 170 miles. 0 problems and absoulte beast compared to stock drive train on 22 turbo levo

 

[Stoneilove]

yeah possibly, it was working fine up until about 2 weeks ago, then just this strange non-response. I feel like it happens when I get into super rough ground, maybe the thing thinks its been hit and disconnects??

Id send it back mate it should run mint, sounds like a faulty mech.

 

[Kenevieve]

I have 3 axs batteries and one of them seems to do same thing. So it maybe battery related and that one which is causing problems in shifter works fine in axs dropper.

 

[Mikerb]

I have covered nearly 400 miles on my Whyte E 160RSX fitted with GX AXS as standard. It has worked flawlessly throughout. I do however remove the battery every few rides and clean it plus the area in which it fits. Despite the guard dust etc does get into the corners and that could easilly stop the battery fitting properly over time. I also use a stiff brush to clean the pivots and spring and put a little drop of chain oil on each pivot when I clean the bike....wiping away any excess. ( Same routine I use on a standard mech). I dont wait for flashing red light on the mech before charging the battery.........I charge it a bout every 12 hours of riding..........and use the red guard piece on the mech whilst the battery is out on charge. So its a bit more maintenance intensive than a cabled mech but in my book totally worth that extra bit of time for the flawless operation it maintains.

 

[Giff]

I fitted the upgrade to my e160 a couple of years ago and the battery ran out twice during rides. I bought a spare and that lasted several rides…..obviously a dodgy battery but i didn’t realise and thought I had to charge each ride.
My new Whyte with AXS is perfect.
I would suspect the battery.

 

[Stihldog]

Ps I would advise against using any abrasive to clean the battery contacts. That will destroy the contact surface layer which is either a precious metal or special coating. Just use contact cleaner and a soft brush...and wipe with a clean rag or tissue.

I agree. Sometimes those contacts have a Gold layer of metal on them to insure the best possible contact. Do not use anything abrasive to clean them.

A wipe with a soft cloth or someone else’s toothbrush does the trick. Make sure they move slightly in/out (spingy).

 

[Stihldog]

A motion sensor could cause a similar problem, that’d be a possible warranty claim.

 

[Jay Bird]

Could also try to unpair it then repair it over Bluetooth. Worth a try.

 

[Downhillr]

Cookie,

Have you checked the contact prongs on the derailleur? It sounds like the battery is loosing electrical contact with the derailleur. The two prongs on the derailleur are supposed to move freely. If they are sticking or dirty this might be the cause. Check the prongs to see if they are sticking and not moving freely.. I would also buff the contact points with a piece of fine steel wool to clean them up.

It’s a shot in the dark, but worth trying.

Rod

A riding buddy had same issue, cleaned the prongs and applied dielectric grease… no problems since (we both also use the grease on motor battery contact points, around seal for exterior charge port, etc). Dielectric fights corrosion, keeps electrical contacts working when wet as well.

 

[MountainBoy]

Hi everyone,

I got the GX upgrade kit recently and for the most part have been very happy with it. However, I've recently had a few times where shifting stops working while riding and having to pull the battery to get it running again. It seems to happen on really rough trails so I wonder if the battery is not connecting fully even though it has the latch locked.

any thoughts on this, its getting a bit annoying and I am thinking of going back to cables..

This one ride below, I could not get it shifting again. but it was fine once I got home and shut everything off
View attachment 106672

Is it the OEM battery or a replacement? There are counterfeits out there that might not seal water and contaminants as well around the rubber seal.

 

[beanzz]

someone else’s toothbrush

Love the specification

 

[High Rock Ruti]

I’m planning an AXS upgrade so this is good info….watching

High Rock Ruti

SRAM just warrantied my AXS 12 speed with 300 miles, if this derailleur fails again I'm removing it and installing an 11 or 10 speed mechanical derailleur. The AXS has never worked acceptably. I don't understand why, I've got a 2016 Pivot Shuttle with Di2 that works flawlessly, love my AXS dropper best dropper I've ever used, we'll see about the derailleur, I'd look for other's who've removed there AXS drivetrain I'm not alone in the experience.


Warm Regards Ruti

 

[cookie70]

just quick followup, I gave it a good clean with alcohol and have not experienced dead derailleur since.. fingers crossed!

 

[Mteam]

I had similar, I found that there was a small amount of dirt around where the battery sits in the derailleur, causing the battery to intermittantly lose contact with the derailleur. I took the battery off and thoroughly cleaned the whole areas where the battery sits with a toothbrush and pick in the corners,and it's been fine since.

 

[Uktonyb77]

Had exact same issue as described. Open support ticket with sram which spanned two week period of back ond forth. My axs was out of warranty as originally had it on my Santa Cruz before moving onto my e bike.

So long and short. Tried everything , new batteries , cleaning contacts , getting rid of all dirt in battery area corners.

Issue ended up to be what sram refer to as the POGO pin which is that springy little contact on the axs.

The board does come off but they don’t sell a serviceable part to replace it. They were also unhelpful giving me the spec of pogo pin required to desolder old and resolder new. They claimed they couldn’t tell me due to R&D ; pretty poor. So I desoldered pins from the charger , resoldered them to the axs removing the old ones in the process . Admittedly it meant I needed to buy a new charger but that was only £29.99 compared to dumping say £400 on a new axs derailleur.

Not saying it’s your issue but it was mine and had same intermittent weird cutting of the axs and then would have to remove battery and reseat. This went on for about 3 months before derailleur finally just gave up. I’m still on original battery after replacing the pogo pins and no cut outs whatsoever since

So process was remove tiny screws to expose circuit board and remove , snip wires yellow & white , desolder old pogo pins , re solder new pogo pins ( from the axs charger ) ensuring you get the yellow & white wire soldered the same way round as before.

Some pics of the part I refer to

Tony

 

[Jay Bird]

Had exact same issue as described. Open support ticket with sram which spanned two week period of back ond forth. My axs was out of warranty as originally had it on my Santa Cruz before moving onto my e bike.

So long and short. Tried everything , new batteries , cleaning contacts , getting rid of all dirt in battery area corners.

Issue ended up to be what sram refer to as the POGO pin which is that springy little contact on the axs.

The board does come off but they don’t sell a serviceable part to replace it. They were also unhelpful giving me the spec of pogo pin required to desolder old and resolder new. They claimed they couldn’t tell me due to R&D ; pretty poor. So I desoldered pins from the charger , resoldered them to the axs removing the old ones in the process . Admittedly it meant I needed to buy a new charger but that was only £29.99 compared to dumping say £400 on a new axs derailleur.

Not saying it’s your issue but it was mine and had same intermittent weird cutting of the axs and then would have to remove battery and reseat. This went on for about 3 months before derailleur finally just gave up. I’m still on original battery after replacing the pogo pins and no cut outs whatsoever since

So process was remove tiny screws to expose circuit board and remove , snip wires yellow & white , desolder old pogo pins , re solder new pogo pins ( from the axs charger ) ensuring you get the yellow & white wire soldered the same way round as before.

Some pics of the part I refer to

Tony

View attachment 107166 View attachment 107167 View attachment 107168

Did you remove and reinstall these pins/screws??? to get the board out?

 

[Stihldog]

Nice save on the pogo pins btw. And thanks for the pics. I’m now checking the movement of those pogo pins each time I recharge and for the occasional debris in that area.

I’ve never lost the battery cage or ran out of charge. Having an AXS reverb helps with any dead-battery anxiety too.

These are definitely pricey upgrades and worth taking care of. My friends and neighbours are beginning to see the benefits and are slowly switching over. They do add a bit of weight though but on an eMTB that’s ok. Maybe I’ll carry less water and get carbon cranks 🫣 to offset the weight difference.

 

[Stihldog]

Did you remove and reinstall these pins/screws??? to get the board out?
View attachment 107181

Good question. It looks like they are holding the pcb in place. The pogo pin mounting pcb is obviously removable …but how?

 

[RichT]

All very good info. Shouldn’t have to sacrifice a charger to get a pin, but if it works… I’ll probably never run into this since I don’t use my bike that hard, but its good to know.

 

[Emailsucks98]

Another AXS question- has anyone had issues with the B-tension screw backing out, or self-adjusting? I’ve had two rides (both in really muddy conditions) where the drivetrain starts grinding in larger cogs, when I check it’s as if the B-tension screw has released, or suddenly backed out a few turns. Checking with the gauge later, B-tension screw needs to be screwed in a few turns to get back to spec. Then it happens again 6 rides later.