An immobiliser and tracker protect your vehicle in different ways. An immobiliser helps prevent an unauthorised start; a tracker helps locate the vehicle if it is taken. Used together, they provide both start protection and recovery support.
Our S5 Plus brings tracking, driver recognition and tag-based immobilisation together. Casper is a separate PIN-operated immobiliser, which can be considered alongside a suitable tracker when you want a vehicle-button authorisation method.
What does each part do?
| Protection | Main job | What to remember |
|---|---|---|
| Tracker | Location information, alerts and recovery support | Tracking alone does not necessarily prevent a start. |
| Immobiliser | Restricts starting without the required authorisation | It does not provide location tracking on its own. |
| Both together | Start protection plus a way to help locate a stolen vehicle | Check compatibility, monitoring and insurer requirements for the exact setup. |
Why use both?
A vehicle may be taken without being started, for example by being towed. That is why start protection and location tracking can complement one another. Neither guarantees that theft will be prevented or that a vehicle will be recovered, but each serves a useful purpose.
Choose tag-based or PIN-based protection
S5 Plus: No Tag, No Start
Our Thatcham S5 Plus costs £449 including nationwide professional fitting. It combines S5 tracking and Automatic Driver Recognition with immobilisation: an authorised tag must be present for the vehicle to start. Monitoring costs £10.99/month separately.
Our standard S5 has driver recognition and tracking, but does not include this added start protection. The distinction matters when comparing products or checking an insurer’s wording.
Casper: authorise starting with a PIN
The Casper Ghost-Like Immobiliser costs £399 including professional installation. It uses a personal sequence entered through vehicle buttons, rather than a driver tag. Casper itself is an immobiliser, not a GPS tracker; any tracker selected alongside it is a separate product and monitoring arrangement.
Compatibility depends on the vehicle and chosen system. Tell us the make, model and year before selecting a combination. EVs and hybrids can need a different package, so ask us to confirm the suitable option.
Match the exact insurance requirement
Our S7 provides tracking and recovery support. S5 adds driver recognition, and our S5 Plus adds immobilisation. Do not assume that adding an immobiliser turns an S7 tracker into an S5 tracker, or that every immobiliser carries the same certification as a tracker.
If your insurer names a category, specific device or authorisation method, check that the proposed setup meets it. Insurance acceptance and discounts depend on the policy; neither follows automatically from fitting two devices.
Fitting, handover and everyday use
Provide the vehicle details and installation information when ordering. After fitting, make sure you understand the tag or PIN routine, how to use the tracking app where supplied, and who to contact for support. Ask the installer about authorised servicing arrangements and what to do if a tag is lost or a PIN is forgotten.
For a monitored tracker, keep the monitoring arrangement active and contact details up to date. Follow the supplied instructions rather than testing theft alerts or changing vehicle wiring yourself.
Prices above were checked on 18 September 2026; see the product pages for current options. Read our tracker cost guide, use Find my protection, or call 01924 976922 to discuss the right setup.
Not sure what your policy means? Read our examples of insurer tracker requirements before choosing a device.
Frequently asked questions
Does an immobiliser track my car?
An immobiliser on its own does not provide GPS tracking. It restricts starting; a separate or combined tracker provides location information.
Does every S5 tracker include immobilisation?
No. Our S5 provides tracking and driver recognition. Our S5 Plus adds No Tag, No Start immobilisation.
Is Casper operated by a tag or a PIN?
The Casper Ghost-Like Immobiliser described here uses a personal PIN sequence entered through vehicle buttons. It is a separate product from tag-operated options.
Can an immobiliser replace the S5 tracker my insurer asks for?
Do not assume it can. An immobiliser and an S5 tracker serve different functions. Confirm the exact device and category requirements with your insurer.