How to find a hidden GPS tracker on your car

TL;DR

Hidden GPS trackers come in three families: Bluetooth tags like AirTags, battery-powered cellular or satellite trackers magnetically stuck to the frame, and OBD/splice-in trackers hardwired into the car. Bluetooth tags are the easiest to find because iPhones auto-alert on unknown AirTags, and Tile and AirGuard run on Android with manual scans. Magnetic cellular trackers are the hardest: a flashlight, a floor jack, and a hand-sweep of the wheel wells and behind the bumpers catch most of them, and a consumer RF detector catches the rest. If you find anything, do not throw it away. Photograph it in place, then call the non-emergency police line and bring the device with you.

Who actually hides GPS trackers on cars, and what they use

The reason this is worth thinking about is that small trackers are now a commodity. A 2024 academic survey of stalking victims found that "over 40% of stalking victims had been subjected to location tracking by tracker tags," and the paper's authors note that Bluetooth-based tags have been documented in theft, stalking, assault, and homicide cases.^[1] Tile alone has sold "over 40 million devices," and the same paper documents that Tile's offline-finding network piggybacks on "33 million smartphones" through Life360.^[1] Apple, for its part, has publicly stated that "AirTag is designed to discourage unwanted tracking," and the same page says "if someone else's AirTag finds its way into your stuff, your iPhone or Android phone will notice it's traveling with you and send you an alert."^[2]

Three device families cover almost every GPS tracker you will find on a personal vehicle:

Bluetooth tags. Apple AirTag, Tile, Chipolo, Samsung SmartTag, and Google Find Hub compatible tags. Battery life of one to three years. Use the manufacturer's crowdsourced phone network to report location.^[2]
Battery-powered cellular trackers. Small magnetized boxes the size of a matchbox or a deck of cards. Connect to LTE-M, NB-IoT, or satellite networks and report location on a schedule. Common in repo, fleet, PI, and stalking cases.
OBD-II and splice-in trackers. Plug into the car's diagnostic port under the dash, or get wired into the wiring harness. Draw power from the car, so no battery to charge.

The detection playbook is different for each, and the rest of the guide covers them in that order, from easiest to hardest to find.

Start with your phone: the iPhone and Android alert path

If you suspect a Bluetooth tag, your phone is the fastest first check, and the two platforms work very differently.

Apple's iPhone alerts automatically when an AirTag, a Find My accessory, or a compatible Bluetooth tracker is "separated for a period of time from its owner" and moving with you.^[3] The alert text Apple documents reads "AirTag Found Moving With You," and tapping the alert gives you a "Play Sound" button that triggers a tone on the AirTag itself, plus a "Find Nearby" mode that uses Ultra Wideband to point you at it.^[3] Holding the top of your iPhone against the white side of an AirTag surfaces the device's serial number and the "last four digits of the phone number of the person who registered it," which is what you give police.^[3]

Apple also says the alert mechanism is independent of your phone's own radios: "Disabling Bluetooth, Location Services, or Find My on your iPhone does NOT stop the owner from seeing the device's current location."^[3] The owner's view goes away only when the AirTag is disabled, which for an AirTag means popping the back cover and pulling the CR2032 battery.^[3]

Android works the same idea but with two important caveats. Apple's Tracker Detect app for Android is a manual scanner; it does not run in the background, and a single scan "can take up to 10 minutes to complete."^[4] That 10-minute ceiling also means a quick scan may miss a tracker that has only been near you briefly. Open-source apps like AirGuard scan continuously in the background for AirTag, Chipolo, and other Find My compatible tags, which is closer to what iPhones do automatically.^[1] If you only have Apple's app on Android, plan to keep moving during the scan and accept that the scan will need to be re-run.

Tile and the manual-scan problem

Tile handles unwanted tracking differently, and worse. A 2025 security analysis of Tile's network concluded that Tile's "Scan and Secure" feature "is not a background process, and must be triggered manually in a sub-menu" of the Tile app, and "the scan duration is ephemeral, lasts about 10 minutes."^[1] Reporting on the analysis summarized this as: "the app doesn't scan in the background. The user has to start the scan manually," and "it only works if the user keeps moving around for 10 minutes."^[5]

Tile also runs an "Anti-Theft Mode" that hides a Tile from other people's Scan and Secure scans. The company requires "a government-issued ID, a live photo of the user, and agreement to a $1 million fine if convicted of stalking" before activating Anti-Theft.^[1] Researchers flagged the dual-use risk: "stalkers could abuse the same feature. They would still see the tag's location, while the victim's scan would not detect it."^[5] If a Tile is set to Anti-Theft Mode, your phone will not alert you at all, and a Tile-app scan will not find it. Plan accordingly.

The hand-and-flashlight sweep: where magnetic cellular trackers hide

If the phone alert path came up empty and you still suspect something, you are looking for a battery-powered or wired tracker. The good news is that these devices have to live somewhere on the car, and a small set of spots covers almost every case reported to police and described in stalker-awareness material.^[6] The bad news is that the underside of a car is dark, dirty, and you generally have to get low.

Tools you need:

A bright flashlight and a small mirror on an extendable stick (an inspection mirror from any auto parts store).
A floor jack and two jack stands, or a ramp. Crawling under a car on a jack alone is dangerous.
Latex or nitrile gloves. Under-car surfaces are sharp and covered in road grime.
About twenty minutes and a stretch of flat ground.

Seven exterior spots, in the order they show up most often in reports:^[6]

Inside both front and rear wheel wells. Magnetic trackers are typically zip-tied or stuck to the inner fender, above the tire line so the device does not get ripped off. Feel behind the plastic liner with your fingers; a tracker is a smooth, hard rectangle with a magnetic pull.
Behind the front and rear bumpers. Push your hand up under the plastic bumper cover from below. Trackers ride on flat metal surfaces near the frame rails.
Behind the license plate. Either between the plate and the mounting bracket, or on the rear-facing side of the bracket itself. Lift the plate screws and check the back side.
Inside the trailer hitch receiver. A square recess in the center of the rear bumper. Look up into the receiver with a flashlight; a tracker fits comfortably.
Under the car on flat metal frame rails. Especially behind the fuel tank and around the spare tire well. Run your hand along the bottom of the frame, feeling for anything that is not a rivet or a bracket.
Inside the engine bay. Magnetically stuck to the radiator support, the strut towers, or the firewall. Heat is the reason this is "less common" than the wheel wells, but cheap commercial trackers handle engine-bay temperatures.
Inside or behind exterior trim. Door rocker panels, behind the fuel door, the tow hook cover. Anything that pops off with a plastic trim tool is fair game.

Inside the cabin, three more:

Under the dashboard near the OBD-II port. The OBD-II port is a trapezoidal connector under the dash on the driver's side, almost always within arm's reach without tools. Anything plugged into it is a tracker; anything wired in next to it likely is too.
Inside the glove box, behind the radio, or behind interior panels. Hardwired trackers need 12 volt power and ground. Look near any wiring harness that disappears into the dash.
Inside the trunk near the taillight housings. Another 12 volt tap point. Look for spliced wiring or a small box that does not match the factory trim.

What you are looking for, in every spot, is something that does not belong: a smooth black or gray plastic rectangle 1 to 3 inches long, often with a small antenna, a magnetic base, or a fresh zip-tie. If a fastener looks new (no rust, shiny metal where the rest is weathered), that is also a signal.

RF detectors and bug sweeps: when to bother

A consumer RF (radio frequency) detector picks up the brief cellular or satellite transmission that a tracker makes when it reports its position. Mid-range handheld detectors run $80 to $400 and work best at close range, with the car off and in a quiet environment. A 2025 academic analysis of Tile's network put the device's identifier refresh interval at "every 15 minutes" for Tile tags, with "8640 unique values" rotating inside the broadcast.^[1] A 15-minute refresh means you may need to wait up to that long for the device to broadcast, and a noisy RF environment (parking garage, near a cell tower, near a busy road) makes false positives common.

Practical rules if you go this route:

Turn the car off and put your phone in airplane mode. Your phone is broadcasting constantly.
Walk the detector slowly around the wheel wells, under the car, and through the cabin.
Wait at least one full refresh interval (15 minutes for Tile, often 5 to 10 minutes for cellular trackers) before concluding nothing is there.
Treat a beep as a strong signal to inspect that area by hand. RF detectors cannot tell you what the device is.

For most people, the hand-and-flashlight sweep is faster, cheaper, and more reliable than a consumer RF detector. A professional sweeps by a licensed investigator is more capable than either, and is worth it if you have reason to believe a tracker is being placed repeatedly by someone with technical knowledge.

What to do if you actually find one

Once you have located a suspected tracker, four steps, in order:

Photograph it in place. Multiple angles. Include something with a timestamp (a newspaper, your phone's lock screen). Do not pick it up yet.
Do not destroy it. Disabling it ends the live updates, which destroys evidence. If the device is a Bluetooth tag like an AirTag, Apple's documentation tells you that "after you disable the AirTag, the owner can no longer get updates on its current location,"^[3] which is true, but it also means police lose the link to whoever registered it.
Call the non-emergency police line. A GPS tracker placed by a private individual on a car they do not own is, in several states, a crime in its own right. Michigan's MCL 750.539l, for example, makes "unlawfully placing a tracking device on a motor vehicle" a misdemeanor punishable by "up to 93 days in jail and/or a $500 fine." Other states reach the same conduct through stalking or unlawful surveillance statutes.^[7] If you have an active stalker or abuser, call 911 instead.
Bring the device with you when you report. Officers can pull the IMEI, ICCID, or registration record that points back to the buyer.

If you do not want to involve police and you are certain the device is a Bluetooth tag you can disable yourself, Apple's documentation gives you the safe way: for an AirTag, "remove the battery."^[3] For a Tile with Anti-Theft Mode, there is no consumer-level disable, and you should treat it as evidence rather than as something to remove.

The Bottom Line

Bluetooth tags are an easy first check: an iPhone will alert on an unknown AirTag automatically, and Android users can run Apple's Tracker Detect or the open-source AirGuard app. Magnetic cellular trackers are the next layer, and a floor jack, a flashlight, an inspection mirror, and a hand-sweep of the wheel wells, behind the bumpers, and along the frame rails catches most of them. If you find anything, photograph it, do not destroy it, and call the non-emergency police line with the device in hand.