Racing Transponder Battery Service

Looking for MyLaps & AMB TranX transponder repair? - we are now replacing batteries in the TranX 160/260/MX "Classic" and the old style case that has the four screws. Older style TranX260 transponders batteries can also be replaced, if they use a 3-cell pack we have that covered. We started doing this out of a basic need in our kart club for repairing our rental transponders, and from there it was opened up to others. If you have a transponder that needs repair, please follow the steps on the repair form below or just contact us. If we can't repair your transponder, we will return it at no charge. (It will be tested prior to repairs)

We now use a CNC process to make faster repairs on the "Classic" style case.  The grey/black cap is fully removed and in some cases it may show slight tool marks, usually the repairs will look as good as when you sent it in.  On the top of the transponder we use the CNC with an end mill about the thickness of your fingernail, color matched epoxy helps hide this small groove once we are done.  Overall this helps us make faster repairs, we leave your transponder intact and no longer need to remove it from the case.  A new battery is cycled, tested, and then placed into the transponder.  We let the transponder fully charge, check the voltage and signal strength and once we are happy we close it all up.

Pay after repairs, not before!  We keep you in the loop during the repair process, from arrival through various stages of repair, and ship it back with a USPS priority mail tracking number provided.

Battery Replacement - starting at $55.00

If you transponder is not staying charged or does not work for a whole event, it might be time to replace the battery. Tranx style transponders will blink, and this helps you determine how many days of charge it has roughly remaining.

We use high capacity quality Japanese batteries and soldered them into place, we warranty the battery replacement for one year.

Generally return times are around 2-weeks in the US (usually much less, sometimes it only takes 2-days for the actual repair). If you need rush processing and faster shipping please select that from the options.  (We have done a few overnight repairs with the epoxy still curing to get racers back on track the next day, done a few at the track even)  Normally, we like to take our time and check it all out first!

Important: With USPS shipping they do not like anything that is transmitting a signal, so you will either need to make sure the battery is discharged or ship it in with the charging cradle (wall-wart not needed). The charging cradle will keep the transponder in a sleep mode.

Contact us if you would like to inquire about a club/group discount, the more you send in the better the pricing. We started repairing our club transponders, and we realize when a large amount of transponders need repairs it can break the budget. Our local track had to repair 18 at once for example (over $5k at the time, even more today).

Payments are processed using either a credit card (via Stripe) or PayPal.  Or check our eBay listings if you prefer that system.

Types of racing transponder we repair?

We currently only repair the TranX 160, TranX 260, and MX style transponders. We do not offer repairs on any of the subscription based transponders. Use the picture guide below to match up your model, if you see it we can repair it. New “Classic” transponders did come with a three-year warranty, check with MyLaps to see if you have any time left.


Older style cases that have screws are repairable, some of these will take a 3-cell battery pack instead of just 1-cell.


It is now called the “Classic” case transponder by MyLaps, generally they have a greyish or black cap on the bottom.  They may say AMB, MyLaps, or just TranX.

How are repairs made?

Step One: We check the transponder to make sure it can be repaired, if not you will be notified and it will be shipped back. Thankfully this is rather uncommon, and we have a few fixes available for certain hard faults.

Step Two:

Old Style Case (with screws):
On the older style of transponder we remove the whole inside resin part, the case is then cleaned.  Carefully the old resin is milled away to expose the solder points.

don't do this

In this picture you can see where the customer was using a screw driver to chew away at the material, please don’t do this as it is possible to accidentally hit some of the electronics or wiring (some bits are actually close to the surface, especially on the underside).  You can see that this transponder appears to have a rectangle on the right side, this is actually a 3-cell gum-stick type battery (prismatic).  Normally, you can spot this yourself by removing the top cover. While a single cell is deeper into the resin and sometimes barely visible.  3-cell models can also be spotted when the case on the left side starts to bulge out.  As the layers between the battery cells expand.

Once the new battery is in place we start a cycle first, letting it fully charge before we epoxy things back up.  There are a few different circuit board layouts inside the old case, some may blink backwards in color for 3-cycles even.  Disclaimer: 3-cell repairs normally take around 5 complete charge and discharge cycles before the blink codes return to normal.  During this time as long as you charge it prior to an event, it will work just fine on the track.  If we spot this trait, you will be alerted and given further directions.  We will actually wrap the transponder in an instruction sheet explaining what model it is.

On the inside you will find a warrant date placed in the resin.

Classic style case (no screws):

On the “Classic” style transponder case, we now use a CNC machine to mill out a small hatch.  Around a 1cm square hatch is created, and leaves behind a small groove which is later epoxied.  In this picture you can see the access point once it has been removed.  A custom-built jig holds the transponder firmly while being machined.  See our Instagram feed for a video, or

tranx160_cut open

Step three: Cycle the transponder fully, while checking battery voltages to see how it is actually charging the cells. This initial cycle can take around 24 to 48 hours.  We log the run rates, charge rates, and signal on our spreadsheet (tracks/clubs are kept on their own tab and provided in the box).



Step four: After being happy with the function of the replaced battery, resin is added to protect the internals keeping it weather tight and safe from the vibrations of racing.

Here is a later stage of the repair with the hatch being placed back, and color matched epoxy is used to clean it all up.  This picture was with a 1/16″ end mill, which is no longer used.  New repairs feature a much smaller groove at just 1/32″, helping to keep it all a bit nicer looking in the end.

tranx160_case being glued

Step Five: Unit is shipped back to you using USPS, other shipping services are optional . A warranty and care card is included in the package, sticker for your charging cradle, along with the warranty date being added to our database.

Important: Along each step of this repair process we will send you an email or txt notification keeping you updated on the progress.  If our repair volume is greater than normal we will let you know or post it on our website in advance.

Payment methods:

We like the process of only charging you after the unit is ready to be shipped back, in our final email we will include an invoice which can be paid a few different ways.

 Preferred Methods of payment
eBay can be used – see these two listings

TranX 160 – eBay Link

TranX 260 – eBay Link

PayPal Invoice
Through our online store system which takes major credit cards (via Stripe) and PayPal  (ECWID is the store provider)
You can include a check when you mail in the transponder, normally this by your request only. Suitable for larger orders, club repairs, etc.

If you are more comfortable using eBay that is great, payment in advance is ok as well. In the event a transponder is not repairable, you would then be refunded if you used that method.

Bulk Discounts?

We do offer bulk discounts, not only does it help save on shipping costs on both sides.  It additionally helps clubs afford repairs or avoid upgrading or buying replacements.

Even if a group of racers wants to go in together to send in three or four, send us an email and ask.

If you are a club that needs to repair 20 or 30, let us know and we can provide you with a bid or other info for your board or club to look at.

If you own a local race shop and want materials to display, we would be more than happy to send you something.


How long will my repair take?

Ideally we like to say around 2-weeks (normally much less).  You will be notified of each step, any delays or problems, etc.

A short breakdown basically gives us the following:

Day 1: Pictures and quick tests to see if transponder is working. Old style will then be removed from the case bottom, while the ‘Classic’ will go over to the CNC machine. You will be contacted or sent a txt message at this stage. Cases are washed and checked for cracks.

Day 2: Testing with the old battery now removed, checking how the transponder is charging on a test rig and running/giving a signal. We log all of these numbers on our spreadsheet, tracks/clubs are kept on separate tabs.

Once the transponder checks out, we will proceed with removing enough material for installing the new battery. We want to make sure the battery is fully surrounded by resin, keeping it safe from the elements of racing and vibration. We do not use silicone or hot glue for our repairs. We do not cut the case in half (as seen on YouTube) as we found that repair style to allow liquid to still enter the battery area, leading to failures.  We also found the battery was not fully surrounded with resin, air pockets would form around the battery allowing damage.

This is why we only use a CNC process on the ‘Classic’ transponder, while the Older style takes a mix of hands on work and rotary tools (like the dentist!).

Day 3: Transponder is on a discharge cycle with the new battery. We prepare each battery prior to this step, bringing the pack down to the correct voltage, in some cases it still may take around 3-days for the transponder to shut off.

Day ~4: Transponder if dead goes on a full charge cycle.

Day ~5: Battery voltage is checked to make sure the target voltage was reached, signal is checked. You will be contacted at this stage with updates. Depending on the model we will secure it for being filled with resin, place the access hatch back on from the CNC process, etc.

The resin sets rather quickly (3-mins or so), so morning repairs at this stage will go out for shipping that day.

2 to 3-days for return shipping.

Sometimes depending on what part of the day it arrives from the mail, it can be turned around that week. Depending on how many transponders we have on the bench for work, the above steps may take less time.


What is the warranty?

Our warranty covers any battery faults, maybe a cell develops an issue and fails early.  If that happens within a year we will fix it.  We do ask that you read the warranty card for care instructions to help get the longest life from your replacement. For best life charge once per month, unplug the cradle from the wall. Or see our ‘Transponder Saver’ device.

If the case separates or the bottom cap comes loose, we will fix that. (rare)

The cells we use should go another 10+ years.  I did test some different Chinese cells for example, and those failed within a year and were from different companies.  It was interesting to run that test to see the difference in quality.  None of those cells were used outside of a few test cases that were local to our home track.

If you need warranty service, let us know and we will email you a paid return shipping label.  We will cover the shipping both ways in a case like this.

What is not covered: things like abuse, dragging the transponder for many laps, etc.  Additionally our repairs do not go near any of the actual transponder parts, we target just the battery area and avoid where we know all the other parts are.

We have fully taken apart a few test transponders to map out where all the important bits are, and have built jigs to help keep the tooling away from those spots.


What other repair options do you offer?

As a free value added service we fully clean the cases, trying to get them looking as new as possible.  The warranty card also has some tips that you can use at home to keep them clean.

We can also cut a new vinyl sticker to replace worn or torn ones.  Custom designs are extra, just let us know if you have an idea for it.


Below is a great before, during, and after picture.


LED replacement is an option, if for example you only see one color blinking (maybe green went out, or both).  We can replace that on both case styles.  We are designing a transponder cradle that will have a test button and accept both styles of case, more news and pricing on that soon.  It will be an option instead of replacing the LED.


Swapping cases – if your case is badly damaged and we have a suitable donor case it is possible to make that happen on both the old style, and classic style case.


We are not associated or endorsed by MYLAPS - Check with them to see if your transponder is still under warranty (usually 3-years) first. We do provide a one year warranty on the battery repairs and any separation in the case from our repairs. We do not cut the case open, but the cap will be epoxied back into place after repairs are completed. If your transponder does not work after the battery replacement it will be returned at no charge, normally it is the battery that needs replacement but in rare cases the transponder could have another error.