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Specialized turbo levo comp — Problem with battery. Took battery from bike and 3rd...?

bazza5566

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Hi everyone, new member here.

I am looking at a Specialized turbo levo comp.

Problem with battery. Took battery from bike and 3rd light flashing on battery. Charger says red for approx 25 minutes then starts flashing. Any ideas?
 
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Hi everyone, new member here. I am looking at a Specialized turbo levo comp. Problem with battery. Took battery from bike and 3rd light flashing on battery. Charger says red for approx 25 minutes then starts flashing. Any ideas?
Welcome to the forums, @bazza5566. The third LED flashing on a Specialized battery is unfortunately a fairly well-known fault indicator, and combined with your charger going red then blinking, it points towards a BMS (Battery Management System) issue rather than a simple flat cell.

On the Gen 2 (2019-era) Levo, this specific pattern of the 3rd green LED flashing is a recognised failure mode where the BMS locks up. There are specialists who can sometimes unlock these, so it's not necessarily a death sentence for the battery, though it does need attention beyond what a normal charger cycle can fix. On earlier Gen 1 504Wh batteries, a similar symptom (three red lights blinking with beeping) has occasionally been recoverable by pedalling the bike quickly for about five turns to nudge the BMS back to life, though that's a long shot depending on your generation.

A couple of things worth establishing first: do you know which generation Levo Comp this is? The year model makes a big difference to what's going on internally and what the fix options are. Also, has the bike had any recent firmware updates or been sitting unused for a long period? One community member found their battery got bricked after a dealer firmware update via the Mission App, and Specialized couldn't resolve it. Prolonged storage at very low charge can also trigger BMS lockouts.

It's also worth checking the charging port itself. One owner traced a near-identical 3rd LED blinking issue during charging to a magnetic particle stuck in the charging port, which was causing a pin short. A quick inspection with a torch and a careful clean could save you a lot of grief.

If this is a bike you're looking at buying rather than one you already own, I'd treat that flashing LED as a significant red flag on the asking price. Battery replacements aren't cheap, and a locked BMS needs either a specialist or a warranty claim. Happy to help narrow down the diagnosis further if you can confirm the year and model.
 
Thanks. I bought the bike new in 2022. I have not used it since september due to work & life getting in the way. It has not had a firmware update and was probably connected to mission control in August. Replaced battery in tcu approx August. Do you know of anywhere that checks them, preferably northern england but willing to post if needed.
 
Thanks. I bought the bike new in 2022. I have not used it since september due to work & life getting in the way. It has not had a firmware update and was probably connected to mission control in August. Replaced battery in tcu approx August. Do you know of anywhere that checks them, preferably north...
Right, a 2022 Levo Comp that's been sitting since September makes perfect sense for this symptom. Lithium cells really don't enjoy being left at low charge over winter, and if the battery was already partially depleted when you parked it up, a few months of self-discharge could have pushed one or more cells below the voltage threshold where the BMS decides to lock things out as a safety measure.

The TCU battery swap in August shouldn't be related to the main drive battery issue, so I wouldn't worry about that being a factor. For getting the battery assessed and potentially recovered, there are a few options in the north of England worth looking into.

Additionally, a 2022 Levo Comp sitting since September lines up well with a BMS lockout from prolonged low-charge storage. Lithium cells self-discharge slowly, and if the battery was already down to, say, 30-40% when you parked it, five months of sitting through winter could have dragged one or more cell groups below the BMS's low-voltage cutoff threshold. At that point the BMS locks out charging as a safety measure, which is exactly what you're seeing with the charger going red briefly then blinking.

Before you send it anywhere, one thing worth trying: remove the battery completely, disconnect all cables, and let it rest unplugged for 10 to 30 minutes to allow the BMS to potentially clear its fault state.

Then reinstall and try a full uninterrupted charge. It's a long shot with a Specialized battery given how locked-down their BMS is, but it costs nothing and five minutes.

For professional diagnosis, there are a few options. Your first port of call should be your local Specialized dealer, since a 2022 bike may still have some warranty coverage on the battery (Specialized typically offer a two-year warranty, so you'd be right on the edge depending on exact purchase date). Even if it's just expired, they'll have the diagnostic software to read the battery's internal state and tell you exactly what's gone wrong.

If the dealer route draws a blank or quotes you the Earth for a replacement, there are independent specialists who handle this sort of thing.

Big Game Bikes offer a professional eBike battery diagnostic and repair service starting from £75, which includes battery collection, full diagnosis, and return shipping, so you wouldn't need to travel.

TECH-NIC Repairs also offer BMS and cell balancing services, claiming an over 90% success rate on battery recovery. Worth noting though that

they state "Bosch, Yamaha and Shimano are not currently repairable due to their anti-repair design", and Specialized's proprietary battery may fall into a similar category depending on how locked the BMS is. Give them a ring first to confirm they can work on Specialized packs before posting anything off.

UK Battery Repairs is another option that specialises in lithium battery diagnosis and repair with a mail-in service.

And if you happen to be near the Midlands, there are recelling specialists in the Wolverhampton and Nottinghamshire area that come recommended on the Pedelecs forum, though quality can vary wildly with independent cell work.

Whichever route you go, do check that warranty date first. If you bought new in 2022 and it's been stored properly (indoors, not a freezing garage), Specialized may well cover this. It's worth a conversation with the dealer before spending anything.
 
Right, a 2022 Levo Comp that's been sitting since September makes perfect sense for this symptom. Lithium cells really don't enjoy being left at low charge over winter, and if the battery was already partially depleted when you parked it up, a few months of self-discharge could have pushed one or more cells below the voltage threshold where the BMS decides to lock things out as a safety measure.

The TCU battery swap in August shouldn't be related to the main drive battery issue, so I wouldn't worry about that being a factor. For getting the battery assessed and potentially recovered, there are a few options in the north of England worth looking into.

Additionally, a 2022 Levo Comp sitting since September lines up well with a BMS lockout from prolonged low-charge storage. Lithium cells self-discharge slowly, and if the battery was already down to, say, 30-40% when you parked it, five months of sitting through winter could have dragged one or more cell groups below the BMS's low-voltage cutoff threshold. At that point the BMS locks out charging as a safety measure, which is exactly what you're seeing with the charger going red briefly then blinking.

Before you send it anywhere, one thing worth trying: remove the battery completely, disconnect all cables, and let it rest unplugged for 10 to 30 minutes to allow the BMS to potentially clear its fault state.

Then reinstall and try a full uninterrupted charge. It's a long shot with a Specialized battery given how locked-down their BMS is, but it costs nothing and five minutes.

For professional diagnosis, there are a few options. Your first port of call should be your local Specialized dealer, since a 2022 bike may still have some warranty coverage on the battery (Specialized typically offer a two-year warranty, so you'd be right on the edge depending on exact purchase date). Even if it's just expired, they'll have the diagnostic software to read the battery's internal state and tell you exactly what's gone wrong.

If the dealer route draws a blank or quotes you the Earth for a replacement, there are independent specialists who handle this sort of thing.

Big Game Bikes offer a professional eBike battery diagnostic and repair service starting from £75, which includes battery collection, full diagnosis, and return shipping, so you wouldn't need to travel.

TECH-NIC Repairs also offer BMS and cell balancing services, claiming an over 90% success rate on battery recovery. Worth noting though that

they state "Bosch, Yamaha and Shimano are not currently repairable due to their anti-repair design", and Specialized's proprietary battery may fall into a similar category depending on how locked the BMS is. Give them a ring first to confirm they can work on Specialized packs before posting anything off.

UK Battery Repairs is another option that specialises in lithium battery diagnosis and repair with a mail-in service.

And if you happen to be near the Midlands, there are recelling specialists in the Wolverhampton and Nottinghamshire area that come recommended on the Pedelecs forum, though quality can vary wildly with independent cell work.

Whichever route you go, do check that warranty date first. If you bought new in 2022 and it's been stored properly (indoors, not a freezing garage), Specialized may well cover this. It's worth a conversation with the dealer before spending anything.
Thanks. I will give that a try tomorrow. I have the battery out of the bike at the moment and had it sitting next to a radiator to see if that made a difference. Will put it in bike in morning and try the pedal thing to see if that works. I think it has only had approx 20 charge cycles as when i go out its quite level in places so i like to push myself with no assist on slight gradients then put assist on when approaching a climb. On other days if we go to the forest it gets used more. When i took it for its 1st service they said that all the info is stored in the battery so hopefully they can access it.
 
Thanks. I will give that a try tomorrow. I have the battery out of the bike at the moment and had it sitting next to a radiator to see if that made a difference. Will put it in bike in morning and try the pedal thing to see if that works. I think it has only had approx 20 charge cycles as when i go ...
Good plan, @bazza5566. One small note on the radiator approach: gentle warmth won't hurt, but don't leave the battery right up against a hot radiator for extended periods. Lithium cells don't love sustained heat any more than they love deep cold. Room temperature is ideal for what you're trying to do.

With only around 20 charge cycles on a 2022 battery, the cells themselves should be in excellent health. That's barely broken in. The issue is almost certainly the BMS locking out rather than any actual cell degradation, which is good news because it means the battery is likely recoverable rather than needing replacement.

You're right that the battery stores all the diagnostic data: charge cycles, cell voltages, error history, the lot. When you take it to a Specialized dealer, their diagnostic tool can read all of that and tell you exactly what state each cell group is in and what triggered the lockout. Given the bike was bought new in 2022, it's worth checking your exact purchase date against Specialized's warranty terms. You could be right on the edge of coverage, and if you're even a week inside it, that's a free fix rather than an expensive one. Dig out the receipt before you go.

One other thing: for future storage, the sweet spot for lithium batteries is around 50-60% state of charge, stored indoors at room temperature. That gives enough headroom that natural self-discharge over a few months won't drag the cells below the BMS threshold. Worth knowing for next time work and life conspire to keep you off the bike for a season.

Let us know how you get on with the pedal trick and the dealer visit. Fingers crossed it's a straightforward reset.
 
Will do. Purchased Feb 28 2022 so fingers crossed. Thank you very much for your knowledge.
 
Will do. Purchased Feb 28 2022 so fingers crossed. Thank you very much for your knowledge.
February 28th 2022, so you're just about four years in now. Specialized's standard battery warranty is typically two years, which would have expired February 2024, so you're likely outside that window unfortunately. That said, it's always worth asking the dealer directly, as some have been known to show goodwill on battery issues, particularly when the cycle count is as low as yours. Twenty cycles on a four-year-old battery is practically museum-condition.

Either way, the dealer diagnostic is still your best first step since they can read the exact cell voltages and error codes, and that information is useful whether it ends up being a warranty conversation or a quote from an independent specialist. Good luck with the pedal trick in the morning, and let us know how it goes, @bazza5566.

EDIT: @bazza5566 reports If purchased February 28, 2022, the battery would be closer to 2-3 years old, not 'just about four years in now.'. Not yet independently verified — take with a pinch of salt.
 
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Will do thanks. Will this need to go to the shop where i got the bike or any specialized dealer?
 
Will do thanks. Will this need to go to the shop where i got the bike or any specialized dealer?
Any authorised Specialized dealer can help you, @bazza5566. You don't need to go back to the shop where you bought it. The diagnostic software they use is standard across the dealer network, so whoever is closest or most convenient to you will be able to plug in, read the battery's error history and cell voltages, and give you the full picture.

That said, if you still have a relationship with the original shop and they know the bike's history, it can sometimes smooth things along, particularly if there's any goodwill conversation to be had about the battery given your very low cycle count. But technically, any Specialized dealer will do the job.
 
Good plan, @bazza5566. One small note on the radiator approach: gentle warmth won't hurt, but don't leave the battery right up against a hot radiator for extended periods. Lithium cells don't love sustained heat any more than they love deep cold. Room temperature is ideal for what you're trying to do.

With only around 20 charge cycles on a 2022 battery, the cells themselves should be in excellent health. That's barely broken in. The issue is almost certainly the BMS locking out rather than any actual cell degradation, which is good news because it means the battery is likely recoverable rather than needing replacement.

You're right that the battery stores all the diagnostic data: charge cycles, cell voltages, error history, the lot. When you take it to a Specialized dealer, their diagnostic tool can read all of that and tell you exactly what state each cell group is in and what triggered the lockout. Given the bike was bought new in 2022, it's worth checking your exact purchase date against Specialized's warranty terms. You could be right on the edge of coverage, and if you're even a week inside it, that's a free fix rather than an expensive one. Dig out the receipt before you go.

One other thing: for future storage, the sweet spot for lithium batteries is around 50-60% state of charge, stored indoors at room temperature. That gives enough headroom that natural self-discharge over a few months won't drag the cells below the BMS threshold. Worth knowing for next time work and life conspire to keep you off the bike for a season.

Let us know how you get on with the pedal trick and the dealer visit. Fingers crossed it's a straightforward reset.
Hi Greg, just a follow up regarding battery fault. Took bike & charger to Specialized dealer in durham who checked charger & battery. Battery found to be knackered. They contacted rider care from specialized who gave discount on new one. £720 for battery and they wavered all costs for diagnostics and all updates with latest firmware. Also another 2 year warrentee with new battery. Thanks for all of your advice.
 
Hi Greg, just a follow up regarding battery fault. Took bike & charger to Specialized dealer in durham who checked charger & battery. Battery found to be knackered. They contacted rider care from specialized who gave discount on new one. £720 for battery and they wavered all costs for diagnostics an...
Good result, @bazza5566. That's about as tidy a resolution as you could hope for with a dead battery outside warranty.

£720 with the diagnostic and update costs waived is a decent outcome. Specialized Rider Care don't always play ball, so getting a discount and having the labour absorbed is worth noting. The two-year warranty on the new battery is standard for a replacement unit, though I'd double-check the exact terms with the dealer rather than take my word on the specifics.

Firmware updated at the same time is a bonus too. Worth connecting to Mission Control once you're back riding and keeping an eye on it going forward, ideally topping the battery up to around 80-90% if it's going to sit for more than a few weeks.

Glad you got it sorted. Enjoy getting back out on it.
 
I'm having the same problem. 700Wh battery with flashing third LED. I read about some company replacing the BMS with a compatible one. Can you tell me anything about this?
 
I'm having the same problem. 700Wh battery with flashing third LED. I read about some company replacing the BMS with a compatible one. Can you tell me anything about this?
The flashing third LED on a Specialized 700Wh battery is a well-documented fault pattern, @CiDi. As you can see from bazza5566's experience earlier in this thread, Specialized eventually replaced his under a goodwill discount, but the root cause is almost always a locked BMS rather than dead cells.

Which brings us neatly to your actual question. Yes, there are people doing BMS repairs on these batteries. @cream posted about this directly: "Specialized batteries CAN be repaired. Most M2 batteries with 3rd led blinking when charging have good cells inside and a locked BMS" - they claim they can unlock and repair the BMS so the battery functions again. That's worth investigating if Specialized's official route (new battery at £1,080+) doesn't appeal.

Given your background with Bafang M510 builds and configurable systems, you'll appreciate that the Specialized BMS is considerably more locked down than what you're used to. A straight BMS swap to a generic unit isn't trivial because Specialized's battery communicates with the motor controller over a proprietary protocol. Replacing the BMS with an off-the-shelf board would likely mean the motor refuses to talk to the battery. The unlock/repair approach @cream describes is the more viable path, as it keeps the original BMS hardware intact.
 
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