Turbo Tero Not Charging Despite Green Light?

[gggGary]

Hi, not charging green light is on

I've got a specialized turbo tero.

 

[Greg Watts]

Hi, not charging green light is on I've got a specialized turbo tero.

Welcome to the forum, @gggGary. Let's get your Tero sorted. On the Specialized Turbo Tero, the charger LED turns green when charging is complete, so a solid green light straight away means the charger thinks the battery is already full. If it genuinely isn't, here's what to work through:

1. Clean the charging contacts. Make sure the charging socket and plug are clean and dry before connecting.

Dirt or moisture on the pins is the most common cause of this. Give both the charger plug and the bike's charge port a wipe with a dry cloth. Even a thin film of grime can stop the handshake.

2. Check plugging order. Always power off the bike before charging, connecting, or disconnecting the battery.

Make sure the bike is off via the TCD, then plug the charger into the wall first, then into the bike. Some Specialized chargers are fussy about the sequence.

3. Confirm the battery charge level. If you have the Specialized Mission Control app, check the actual state of charge. It's possible the battery really is full and you're chasing a ghost.

4. Try a different wall outlet. Sounds obvious, but a dodgy socket or extension lead can cause the charger to default to green without actually delivering power.

If none of that works and the red LED on the charger is flashing, that indicates a charging error and Specialized say to disconnect and contact your authorised retailer.

 

[gggGary]

"Greg" started this thread. The battery is down to 43% now bike works, rides, display, all good. The dealer I bought the bike from folded. Chargers are $200 so a rather expensive what if it's just the charger? A big question is what's the third contact function, hows it wired? 'There's plenty of generic 42 volt 4 amp chargers in the 20-30 dollar range.
Gotta admit; oddball bespoke type parts, connections get me irritated.

 

[Greg Watts]

"Greg" started this thread. The battery is down to 43% now bike works, rides, display, all good. The dealer I bought the bike from folded. Chargers are $200 so a rather expensive what if it's just the charger? A big question is what's the third contact function, hows it wired? 'There's plenty of gen...

Good, I've got what I need. The third pin on the Tero's Rosenberger connector is a data/communication pin, and there's solid community evidence about what happens when it's compromised. Let me put this together properly for @gggGary.

Good questions, both of them. Let me work through this. The third contact is a data/communication pin.

The data pin has to engage before the power pins are enabled - it's a handshake that prevents arcing if you disconnect under load. On the Tero, the power brick connector has only one data pin.

So if that pin is dirty, slightly bent, or making poor contact, the charger sees no handshake and defaults to green - thinking the job is done before it even started. That's almost certainly what's happening to you.

On the generic 42V 4A charger question: your frustration is completely understandable, but there's a reason to hesitate.

The Tero uses a Rosenberger plug, which is a proprietary magnetic connector with that data pin built in. A generic charger won't have it, which means the battery management system won't get the handshake it expects. You could end up with exactly the same green-light-no-charging problem, or worse, no BMS oversight during charging. The risk isn't worth the $170 saving.

Before spending anything, check that data pin. The data pin on the Tero connector appears longer than the recessed power contacts, but the pins on the bike-battery side are all exposed.

 

[gggGary]

Good, I've got what I need. The third pin on the Tero's Rosenberger connector is a data/communication pin, and there's solid community evidence about what happens when it's compromised. Let me put this together properly for @gggGary.

Good questions, both of them. Let me work through this. The third contact is a data/communication pin.

The data pin has to engage before the power pins are enabled - it's a handshake that prevents arcing if you disconnect under load. On the Tero, the power brick connector has only one data pin.

So if that pin is dirty, slightly bent, or making poor contact, the charger sees no handshake and defaults to green - thinking the job is done before it even started. That's almost certainly what's happening to you.

On the generic 42V 4A charger question: your frustration is completely understandable, but there's a reason to hesitate.

The Tero uses a Rosenberger plug, which is a proprietary magnetic connector with that data pin built in. A generic charger won't have it, which means the battery management system won't get the handshake it expects. You could end up with exactly the same green-light-no-charging problem, or worse, no BMS oversight during charging. The risk isn't worth the $170 saving.

Before spending anything, check that data pin. The data pin on the Tero connector appears longer than the recessed power contacts, but the pins on the bike-battery side are all exposed.

yes suspected as much the magnetic plug is a real issue IE picking up stray metal filings etc. pin is clean, spring action works it seems like it's sticking out far enough to make contact with the bicycle side pins all three on both sides checked cleaned appear healthy.
Related I have misplaced the keys so can't get battery out of bike.

 

[Greg Watts]

yes suspected as much the magnetic plug is a real issue IE picking up stray metal filings etc. pin is clean, spring action works it seems like it's sticking out far enough to make contact with the bicycle side pins all three on both sides checked cleaned appear healthy. Related I have misplaced the ...

@gggGary Right, so the pins look clean and healthy but it's still defaulting to green. That narrows things down.

Given you've cleaned everything and the spring action on the data pin feels normal, there are two likely culprits left. First, the charger itself may have developed a fault on its data line.

The data pin has to connect before the power pins are enabled, acting as a handshake to prevent arcing if you disconnect under load.

If the charger's own data contact has gone high-resistance internally, it'll never complete that handshake and will just sit there glowing green, smugly pretending everything's fine. The only way to test this without buying a $200 charger is to find someone else with a Specialized Turbo (Tero, Vado, Como all use the same charger) and try theirs. Even a Specialized dealer should let you plug in for 30 seconds to confirm.

Second possibility: the BMS inside the battery has locked out charging. The bike still rides because the discharge circuit is independent of the charge circuit.

One Vado owner had an identical symptom where the charger stayed green and wouldn't charge, caused by damaged charging hardware inside the battery itself. If this is the case, a diagnostic via Mission Control might show an error code that doesn't surface on the TCD display.

On the lost keys: if you still have the key code that came with the bike, you can order a replacement key. If you've lost the key code as well, you'll need to replace the entire lock mechanism.

 

[gggGary]

what goes on with the data pin, what does each side need, expect?

 

[gggGary]

how to remove the key lock with out destroying anything?

 

[Greg Watts]

what goes on with the data pin, what does each side need, expect?

@gggGary Right, here's what the search turned up, and it's genuinely useful for your situation. Charger side:

The Specialized Turbo charger connector has 2 larger diameter power pins and 1 smaller data/signal pin. One DIY tester measured a fixed 4.8V on the data wire (the brown cable) from the charger side.

Another owner working on a Turbo Como found that with nothing connected, the charger puts about 6V on the control wire, and when connected to the battery that drops to around 3V.

So the charger side is relatively simple: it presents a low voltage on that single data pin and waits for the battery to pull it down as confirmation.

Battery/bike side: The bike's Rosenberger socket has 2 power pins and 4 smaller contact positions, giving it more pins than the charger uses. The extra pins are for CAN bus communication with the motor/controller during riding, not for charging. For charging purposes, only that single data pin matters.

One Levo owner confirmed that applying +5V to the enable pin wakes the battery for about 60 seconds, but it then shuts off unless the controller continues to communicate with it.

The key takeaway: there's a handshake expected between battery and charger before charging starts, but it appears to use only that single control wire rather than full CAN bus communication.