A solid TPMS light almost always means a tire lost pressure — often just from a temperature swing, not a puncture — and airing up to the door-jamb spec usually clears it. A flashing light is different: that's the sensor reporting a fault, usually a dying battery, and it gets diagnosed with a scan tool before any tire work starts.
The two lights look almost the same on the dash but mean different things. Solid means air pressure — most often lost gradually as temperatures drop, since the light trips at a fixed threshold no matter why the air left. Flashing means the sensor itself is the problem, usually a battery that's finally given out after years of transmitting from inside a spinning wheel — reinflating the tire won't fix that.
Detroit Tire Shop checks which one it is with a handheld TPMS tool before touching a tire, since chasing a phantom pressure leak on a car that actually needs a new sensor wastes a customer's time. The shop doesn't close, so a dash light that comes on during a night drive gets looked at the same night, not the next morning.
Why would the sensor need replacing instead of just resetting?
Each sensor runs on its own internal battery, sealed inside the housing, and there's no way to swap just the battery — when it dies, the whole sensor gets replaced. It's not a reset or a relearn problem at that point; a relearn only re-teaches the car which sensor is in which wheel, and it won't bring a dead one back.
That's the tradeoff of sealing the battery in — better protection from water and road grime, worse serviceability, and it's the same across brands, not just one.
Does a new tire mean a new sensor too?
Not automatically. A working sensor gets remounted into the new tire during the swap rather than replaced, and most vehicles need a relearn procedure afterward so the car's computer maps each sensor to its correct wheel position again. Detroit Tire Shop handles the relearn as part of the tire installation rather than sending a customer to a dealer for it.
Why does my TPMS light come on when nothing's wrong with the tire?
It's usually not wrong — pressure genuinely drops as the air inside the tire cools, and the light is just reporting a real, if temporary, number. Airing back up to the correct pressure clears a solid light; if it comes back within a day or two with no obvious leak, that's worth having checked rather than ignored.
Can I drive with the TPMS light on?
Yes, in the short term — it's a pressure warning, not a mechanical failure, so it's safe to drive to get it checked. Running on genuinely low pressure for an extended period wears the tire unevenly and cuts fuel economy, so it's not something to ignore indefinitely.
How do I know if it's the sensor and not the tire?
A flashing light or a specific TPMS fault message on the dash points to the sensor; a solid light that clears once the tire is properly aired up was just a pressure issue. Detroit Tire Shop can confirm either way with a scan tool — call (313) 631-1567 first if there's any doubt.