Replacing The Coin Battery In the Specialized SL TCU Gen 1

[kahn]

Nobody owns a needle here?

Why are you needling folks?

 

[BioWheel]

OK - got it out. I got some plastic tweezers from Amazon but they can't reach in far enough to get a grip. I used a jewelers screw drive (yes - practially the size of a big needle) and stuck it down the side of the battery and gently 'rolled' it out. The little metal pin in front of the battery pushed down for me and stayed there. I was afraid I broke it but popped back up and all working. On another slightly related topic - I crashed my bike today coming off some wet wood planks causing the handlebars to turn full 180 degrees and pulled the wire out of my Lezyne light. I tried to open the lamp to pull wire back through but case must be glued and I couldn't break the adhesive without really damaging the light. Will order new and splice in. Wish stuff could be opened and fixed.

 

[Marcela]

Wonder how a wooden tooth pick would work. Wouldn't conduct electricity.

 

[Stefan Mikes]

@BioWheel I'm so glad you managed replacing the battery! Sorry to hear about your crash!

@Marcela: An excellent idea!

 

[sierradays]

HI Everyone I took the pry off the rear cover approach. Tried the tweezer approach, didn't work, tweezers were too flimsy. With an exacto pry up each clip on the back cover to release the lid, then lift up and go to the next of the 3 clips, kind of a 3-handed job. Then pop the cover, which is held down with adhesive. This exposes the back of the battery which I use the pointy edge of dig into the batter enough to push it out while holding down the metal retainer tab in the front. The adhesive did hold but the clips look distressed.

If I did this again I would take a straight pin approach and bend the tip enough to act as a claw to pull that edge of the casing on the battery, there is a lip that could be grabbed.

But in the end, the bike fired up and it's on the road again.

Cheers

 

[kahn]

HI Everyone I took the pry off the rear cover approach. Tried the tweezer approach, didn't work, tweezers were too flimsy. With an exacto pry up each clip on the back cover to release the lid, then lift up and go to the next of the 3 clips, kind of a 3-handed job. Then pop the cover, which is held down with adhesive. This exposes the back of the battery which I use the pointy edge of dig into the batter enough to push it out while holding down the metal retainer tab in the front. The adhesive did hold but the clips look distressed.

If I did this again I would take a straight pin approach and bend the tip enough to act as a claw to pull that edge of the casing on the battery, there is a lip that could be grabbed.

But in the end, the bike fired up and it's on the road again.

Cheers

If only US military secrets were as secure!

 

[BlackHand]

As a Spesh-curious, I'd like to know does this render the bike inoperable until the batterty is replaced? doesn't seem like something you'd want to attempt as a field repair..

 

[sierradays]

As a Spesh-curious, I'd like to know does this render the bike inoperable until the batterty is replaced? doesn't seem like something you'd want to attempt as a field repair..

What led me to replace the battery was the bike was stored in the garage for the winter, and it wouldn't turn on. I charged it, and the light came on and seemed brighter but wouldn't stay on. This lead me to find out that the battery needed to be changed in the TCU. So yes, your bike won't work. You could do a field change with the right tools and a good dose of luck. What concerned me when I unplugged the connectors was how frail the wires are., Be very careful when plugging it back in. Kind of like installing a CPU in a motherboard all those little pins, and yes I've bent them.
Good Luck

 

[Stefan Mikes]

As the TCU is the Control Unit, an SL e-bike will not work without the operable battery inside the unit. However, the user will be warned well in advance by low battery messages (blinking LEDs on Gen 1 or by text message on Gen 2) so the chance to be caught in the field unprepared is next to none.

 

[Stefan Mikes]

The operation of removing the spent coin battery might seem complicated to a person who has never been replacing a battery in a watch in previous decades
I recommend to never disconnect the TCU or dismantle it. A needle would do to remove the battery. One only needs to try.
I'm saying the above as a person having "two left hands", that is, very poor with tools and manual work

 

[Prairie Dog]

I just swapped the batteries out of both my wife’s and my Creo TCU. Thanks for the helpful advice @kahn and @Stefan Mikes . In my case, I followed @BioWheel 's method using a jeweler's flat head screwdriver to simultaneously depress the spring and slowly coax the battery out. It went much quicker with the second bike. Toothpicks won’t work as they are too fragile and will break off. Both of the original batteries registered LOW <2.1V on my tester.

 

[Renais]

Did this today on my Creo SL E5. Removed the TCU, compressed the spring clip with a long pin and managed to prise up the battery past the clip. I then banged the TCU against something solid, in my case a chair back covered witha towel and the the battery gradually made its way out. TCU replaced and all A OK

 

[JHShaw]

Yes, infuriating and frustrating. But today this woked nicely: Basically you just depress the retaining clip and tap out the battery. I removed the unit - the TCU cable disconnects easily and lets you separate the unit and hold it comfortably. The retaining clip is at the front of the battery, I held it down with a tiny screwdriver, A toothpick should work, holding with two hands, which allowed me to tap the TCU downward onto a surface with the battery compartment facing downward. I could see that the battery rim had moved outward over the clip, so the battery was free to slide. Then a couple of more taps and it was out. Was easier to do than to describe!

 

[Rixtory]

Here's what I was able to do and it worked well and quickly on my '21 SL5 with 1500 miles:
1. Made sure I had a good 1620 battery - Even though they are still sealed in retail packages, they are sometimes dead when you break them out of their polyethylene prison.
2. Grabbed a pi\air of my wife's make=up tweezers (I think they are eyebrow tweezers. Very Sharp and angled at the end.
3. Covered the ends of the tweezer with scotch tape - folded over each and trimmed to 1/16" on the sides.
4. Grabbed a dental pick, but that was too thick, Had an old pick from a watch kit, so used that, but turns out I didn't really need it.
5. Torx T10 and remove screw for TCU cover
6. replace screw in hole loosely
7. Unplug TCU from harness (GENTLY)
8. Take TCU into house with better light and workbench for elbows
9. Using shielded tweezers, squeezed metal clip that holds the battery, up, and it clicked and seemed to lock in place.
10. Used slim watch prong gently on side of battery to spin slightly. Battery spun easily.
11. Flipped TCU so battery port opening was upside down and pounded my palms together while holding TCU in my hand and battery started to come out.
12. Gently pounded my palms together 1x again and the battery was about 1/4 out - enough to grab it with the shielded tweezers and gently pull it out.
Honestly, at first, I felt like I was taking apart an atom bomb, with all the warning about shorting the battery and TCU out. But it woorked out fine and went back together even easier.
Best Wishes everyone!!!

 

[Stefan Mikes]

Made sure I had a good 1620 battery - Even though they are still sealed in retail packages, they are sometimes dead when you break them out of their polyethylene prison.

Some manufacturers also place a sticker on one side of the battery. That sticker is meant to prevent the battery to be shorten, and it also contains a very bitter compound so kids would not like to swallow the battery. If there is a sticker on the battery, you need to remove it prior to any other action.

Batteries such as the 1620 have a very long shelf life, and that's one of the reasons they are used in miniature electronic devices.