Diagnosis Brief
what this complaint usually turns out to be
what this complaint usually turns out to be
Headlight or Brake Light Not Working — What It Usually Is
How real visits for a light out ended at independent shops across the US — the part actually replaced, how often, and what it cost when it was the only fix.
Bulb
The single most common outcome — nearly half of these visits when combined with the runner-up
Bulb $38 – $146
Light assembly $58 – $262
typical cost when it was the only fix
(parts + labor)
(parts + labor)
| The fix involved | Share of these visits* | Typical cost† | Median |
|---|---|---|---|
| Bulb | $38 – $146 | $73 | |
| Light assembly | $58 – $262 | $130 | |
| Switch | $126 – $344 | $216 | |
| Headlight | $60 – $272 | $131 | |
| Fuse | $56 – $239 | $115 | |
| Other, rarer causes | smaller shares — fuses, sockets, switches, wiring harnesses | varies | — |
*Share of visits whose repair involved this part; combined repairs count toward each part, so shares overlap and don't add to 100%. †Middle half of real invoices when this was the only fix — parts + labor, all vehicle types.
Which one is yours? Listen first
- One light out — A single dark lamp is almost always the bulb.
- Both brake lights out with the third working — The center high-mount light runs its own circuit — both mains dark with it lit points at the brake-light switch at the pedal, not two coincidental bulbs.
- Flickering or dim — Flicker and dimness are connection problems: corroded sockets and grounds.
What to expect from the shop
One light out is a bulb; both sides out, or flickering, is a switch, relay or wiring problem that needs diagnosis. Expect the shop to check the bulb and socket first — corroded sockets are common. A full assembly is quoted when the housing is damaged or the internal wiring has burned.
About this data · How to use this brief
Vehicles all makes and models, US fleet
Data confidence High — large sample, stable shares
Records through July 2026, refreshed continuously
Source paid invoices from independent US repair shops
Data confidence High — large sample, stable shares
Records through July 2026, refreshed continuously
Source paid invoices from independent US repair shops
Take it to the shop. It tells you what the likely answers are and what each one should cost — so when the diagnosis comes back, you already know whether the number fits. Vehicle-specific price reports for the common fixes are on fixdozer.com.