An interlock installed in a vehicle is an alcohol interlock device that controls whether the vehicle can start based on the result of the driver's breath test. When selling such a vehicle, unlike an ordinary sale that ends with handing over the car, several things may remain: the device connected to the vehicle, accessories stored separately, the software that manages the device's records, and inspections or services in progress. In particular, how you handle it depends on whether the device belongs to the vehicle owner or is a rental item the supplier must collect.
Based on the AF-i1 product information, the configuration includes a handset that measures the breath, a control box connected to the vehicle's start control, a communication cable linking the two units, installation wiring, a holder, mouthpieces, and dedicated PC software. But the product configuration does not mean everything transfers straight to the buyer. Before the sale, you need to decide item by item what will be handed over with the vehicle and what will be returned or dealt with separately.
Being attached to the vehicle does not make it part of the handover
If the sales contract says only "interlock device included," it becomes unclear how the stored handset, spare mouthpieces, cables, and user manual are handled, beyond the installed main unit. It is better to first write down what you actually have, separating items installed in the vehicle from items outside it. Checking each item's model name or other identifying information against the sale list also makes it easier to check for missing items after handover.
Next, check ownership and collection conditions in the original purchase, rental, and installation documents. If the device or some accessories are rental items or subject to collection by the supplier, agree on how to handle them with the supplier before deciding to include them in the vehicle price. For items where the contract wording alone does not settle the matter, it is safer to note, among the parties to the sale, which items are still being confirmed and who is expected to answer, rather than promising the buyer they are included.
| Item to separate | What to check before the sale | Example outcome |
|---|---|---|
| Device installed in the vehicle | Purchase or rental terms and collection agreement | Handed over with the vehicle, or set aside for separate collection |
| Accessories stored separately | Original configuration list and items currently stored | Marked as items to include, items to return to the supplier, or items to check as missing |
| Dedicated PC software | Terms of use and support, and how accounts are managed | Confirm separately whether the buyer can take it over |
| Device usage records | Purpose of retention and basis for providing them | Separate records to keep from information to give the buyer |
For software, look at the terms of use, not just the installer
The dedicated PC software is used to manage and download AF-i1 log events and to configure how the device operates. So the fact that a computer or installation file is on the handover list does not let you assume the buyer can keep using the same software or receive support. That is why you need to confirm who the software's user is, how the account works, who receives technical support, and whose name any remaining services are run under.
In sale preparation documents, rather than saying the software is being handed over, you can state its current status concretely, such as "terms of use being confirmed." If the supplier confirms that it allows transfer, pass on the usage guidance the buyer needs within that scope. Conversely, if it does not transfer or has not been confirmed, separate the vehicle handover from the software schedule so the buyer does not mistakenly think they can use it.
Keep the previous driver's test records separate from the equipment
The AF-i1 can store interlock usage events such as vehicle ACC status, engine start, test results, and tamper detection, with date and time information, and the dedicated software can download them. Because these records may include the previous driver's usage history, you must decide separately whether they should be copied wholesale and handed over like an item in the vehicle sale. The buyer needing to know how to use the device is a different matter from the buyer receiving the previous user's test and driving-related data.
You also should not assume that detaching the device, replacing the computer, or closing the account means the records are deleted. First identify what data is stored where, whether any data must continue to be kept, and whether any data is to be provided or deleted. Giving the buyer, separately, only the information needed for future driving, such as how to use the handset, the device configuration, and the inspection schedule, can be a way to avoid mixing records with usage guidance.
Align collection and service schedules before the handover date
The vehicle handover date is the deadline for dealing with the device, but the supplier's collection schedule or an inspection already booked may fall on a different day. If accessories due for collection will remain in the vehicle after the handover date, decide who will keep the items after the vehicle is handed over and deliver them to the supplier. For inspection bookings too, record separately whether you merely requested cancellation and whether the cancellation was actually accepted.
As a hypothetical example, consider a company selling a used vehicle with an interlock installed, handing over the device connected to the vehicle but needing to return a separate handset kept in an office drawer to the supplier. On checking the physical inventory first, the company finds that the vehicle handover documents list only the installed device and leave out the separate handset. This observation means the buyer's scope of receipt and the supplier's return items have been mixed up, so the action needed is to separate the two lists and decide where the handset will be kept and who will return it. Once confirmation of vehicle receipt and the supplier's confirmation of receiving the return are each obtained, the wrap-up criterion for this case is that both sets of items have moved to their designated places.
Mark items complete only after each one has been confirmed
In sale work, it is better not to mark the whole interlock-related process complete just because the vehicle has left. List the vehicle, the installed device, accessories stored separately, software use, usage records, and service bookings one line each, and note the conclusion and basis for each. For example, show the current status concretely, such as "vehicle and installed device handed over," "separate accessories to be returned," and "software transfer terms being confirmed."
The purpose of this list is to show who has to do what. When the items the buyer received, the items the supplier will get back, and the records the previous owner must keep are clear, the vehicle sale and device management do not get mixed up. Rather than switching unconfirmed items to complete, keeping the open questions and the parties who must answer them is a realistic way to define the handover scope that reduces omissions and misunderstandings after the sale.
