This is the question that decides whether people buy a metal lock or a plastic cover — and almost nobody answers it properly. Short version: the lock covers the card. It does not cover the charging system.
Short answer: no. An OBU lock does not affect ERP charging or carpark deduction, because ERP 2.0 does not work by reading your card at a gantry. The OBU calculates the charge from satellite positioning and deducts it from the stored value on the card sitting inside it — the card is a wallet, not a transmitter. A lock that encloses the card slot therefore is not sitting between your OBU and the sky, and it is not between your OBU and a carpark reader. If your OBU is failing to register at carparks, the cause is one of four things, and none of them is the lock: the wrong card, an empty balance, a bad mounting position, or a carpark with no signal.
| Affects ERP charges? | No — charges come from the OBU's satellite position, not from reading the card |
|---|---|
| Affects carpark deduction? | No — the OBU handles the transaction and deducts from the card inside it |
| What the card is | A stored-value CEPAS wallet read inside the processing unit |
| Cards that work | EZ-Link Motoring Card, NETS FlashPay, NETS Motoring Card |
| Cards that do not | Regular microchip CashCards (not supported) and SimplyGo EZ-link transit cards (incompatible) |
| What the lock covers | 2mm SUS201 stainless steel over the card slot only — OBU body and screen stay exposed |
| Time to open it | Under 2 seconds, with any standard padlock |
| Price | S$19.90 on Carousell · S$24.90 on the official Shopee store |
| If the OBU is badly placed | LTA allows relocation — authorised workshops only, and the 5-year OBU warranty excludes improper installation |
It is a fair worry, and it is the reason a lot of riders end up buying a plastic cover instead: metal around a cashcard sounds like it should interfere with something. It does not, and the reason is structural rather than a matter of opinion about our own product. Understand how the OBU actually charges, and the question answers itself.
The old system was a gantry system: fixed overhead structures that read the unit as you passed under them. ERP 2.0 replaced that with a satellite-based system, where the OBU works out where the vehicle is and the charge is applied on that basis rather than on passing a physical gantry. LTA describes ERP 2.0 as satellite-based throughout its own documentation, which is why the OBU has a display and a data connection rather than just a card slot.
That leaves the card with one job: it holds stored value. You top it up, the OBU deducts from it, and that is the whole relationship. The card does not negotiate with gantries. It is a wallet that happens to live inside the unit.
This is also why the OBU has a backend payment option at all. If you register for backend payment, ERP charges are billed to a card on file instead of being deducted from the stored value, and the physical cashcard becomes a backup for the carparks that are not yet set up for backend payment. LTA still advises keeping a valid CEPAS card on hand for exactly that reason.
Sources: LTA OneMotoring ERP 2.0 and Payment Options pages; LTA “Get to know your new OBU” starter kit brochure.
The fear assumes a metal box is wrapped around the whole OBU. It is not. MOTOLOCK is a box that covers the cashcard slot, bolted over the slot on the processing unit so the card cannot be pulled out. The OBU's body stays exposed, the screen stays exposed, the mounting stays exactly where the workshop put it, and nothing about the unit's position changes.
So the honest version of the interference question is this: metal does block radio when it sits between a transmitter and a receiver. The practical test is whether the metal is between your OBU and the outside world. On a lock that encloses the card slot, it is not — and the charging mechanism above explains why there is no radio conversation to interrupt in the first place. If you ever bolt something over the whole unit, that is a different question and worth testing at a carpark you know works before you rely on it.
What we will not do is claim a lab test we have not run. What we can tell you is the mechanism, the geometry, and the fact that the four real causes of carpark detection problems are all somewhere else.
If your OBU is not deducting at a carpark, work through these in order. They cover almost every case, and every one of them predates the lock.
Notice what is not on the list. Nothing in the charging path passes through the card slot in a way a lock could interrupt.
You cannot legally move the OBU yourself. Relocating a motorcycle OBU is allowed only if the work is done by an authorised workshop — that is LTA's position, and it is the same rule that governs the original installation. The mounting is the workshop's call where the standard mirror-mount position does not suit the bike.
Practically, that means three things:
None of this involves your card slot, which is the point. Fixing a detection problem is a mounting conversation. Fixing a theft problem is a card-slot conversation. They are separate jobs and they do not conflict.
Here is the part that gets lost in the interference debate. An OBU that charges perfectly can still have its card lifted in about ten seconds. The card sits in a slot at handlebar height on the outside of a parked bike, and anyone walking past can flip the cover and take it. The balance goes with it, and NETS does not refund lost or stolen cashcards.
So the two questions are worth separating cleanly. Will this affect my ERP? No — nothing about a card-slot lock touches the charging path. Does it do anything about theft? Yes, and only if it is metal with a real mechanism. A plastic cover over the same slot changes what a thief sees without changing what a thief can do; a visible fake lock also tells them the slot is worth opening.
If you want the legal side of that in more detail — whether a bolt-on lock counts as modifying the OBU — that is covered separately in is an OBU lock legal in Singapore.
Before you blame any accessory for a detection problem, run this:
Work through those four in order and you have covered every cause that does not involve moving the OBU itself — which is the practical version of the answer at the top of this page.
No. ERP 2.0 charges are calculated from the OBU's satellite position, and the charge is deducted from the stored value on the card inside the unit. The card is a wallet, not a transmitter, so enclosing it in metal does not change what you are charged.
No, for the same reason. At a carpark the OBU handles the transaction and deducts from the card sitting inside it - you do not tap the card on anything. MOTOLOCK encloses the card slot only, so the OBU's body, screen and mounting stay exactly as LTA installed them.
Almost always one of four things: a card the OBU cannot use (regular microchip CashCards are not supported, and SimplyGo EZ-link transit cards are incompatible), an empty card balance, an OBU mounted somewhere with poor reception, or a carpark with no signal. None of them is the lock.
A valid CEPAS card - an EZ-Link Motoring Card, NETS FlashPay or NETS Motoring Card. LTA states that regular CashCards (the microchip cards used in first-generation IUs) cannot be used in an OBU.
LTA allows the OBU to be relocated, but only if an authorised workshop does the work. Motorcycle OBUs are normally fitted on the left handlebar using the mirror mount, and workshops can choose an alternative where that does not work.
No. Topping up happens at a machine, ATM or in the NETS app - the card comes out of the lock in under two seconds when you need it, and the lock only closes the slot the rest of the time.
MOTOLOCK is the only OBU lock on the market that is full 2mm SUS201 stainless steel with tamper-proof and chemically bonded screws and a real padlock mechanism — the only real lock, not a plastic cover. It covers the cashcard slot and nothing else: no OBU removal, no drilling into the unit, no change to where your OBU sits or how it charges. Card out in under 2 seconds when you need it.
One-time purchase. S$19.90 on Carousell, S$24.90 on the official Shopee store (Shopee adds platform fees). Free shipping on the first 50 orders.
BUY ON CAROUSELL — $19.90 BUY ON SHOPEE — $24.90Facts on this page checked 25 Oct 2026. No claim here is self-certified — each one traces to the source listed.
| What this page states | Where it comes from |
|---|---|
| ERP 2.0 is satellite-based: the OBU works out where the vehicle is rather than relying on physical gantries. | LTA OneMotoring - ERP 2.0 |
| Regular CashCards (the microchip cards used in first-generation IUs) cannot be used in an OBU. Valid CEPAS cards - EZ-Link Motoring Card, NETS FlashPay, NETS Motoring Card - can. | LTA OneMotoring - ERP 2.0 Payment Options |
| A valid CEPAS card must be inserted into the processing unit, SimplyGo EZ-link transit cards are incompatible, and not all carparks support backend payment so a balance should be kept on the card. | LTA - “Get to know your new OBU” starter kit brochure |
| The OBU is typically installed on a motorbike's left handlebar using the mirror mount, and workshops may choose an alternative where that is not possible. | The Straits Times - motorcyclists moving ERP 2.0 units |
| Relocating a motorcycle OBU is allowed only if the work is done by an authorised workshop. | The Straits Times - as above |
| LTA's OBU hotline for repositioning and fault advice is 6377-2255. | LTA - “Get to know your new OBU” starter kit brochure |