How This 2018 Ford F-150's Faulty Taillight Turned Into a $5,600 Repair

How This 2018 Ford F-150's Faulty Taillight Turned Into a $5,600 Repair photo
How This 2018 Ford F-150's Faulty Taillight Turned Into a $5,600 Repair photo

Advanced car features like blind-spot monitoring and cross-traffic alert are great for safety and convenience, but man, it's a bad day for your bank account when they break. Watch mechanic Brian Makuloco show us how a 2018 Ford F-150's broken radio was effectively caused by a taillight water leak, ultimately leading to a $5,600 repair bill.

This 2018 F-150 Limited was a high-feature, fancy model when it came out and qualifies as a luxury car, as far as I'm concerned. Listing at over $60,000, it shipped with pretty much every safety sensor we have now, as well as an exceptionally plush interior. No car is perfect, though I have to say I'd be bummed if I'd plunked down the asking price for one of these only to find its taillights taking on water within five years of its life. But let's back up a smidge, because that's not even where this truck's diagnosis began.


According to the video by way of Ford-Trucks, the vehicle came into the FordTechMakuloco shop for blind-spot warning and cross-traffic alert faults. On top of that, the stereo hard keys and HVAC climate-control buttons were dead.

If you want to get to the good stuff, Makuloco's explanation starts at about the video's 6:00 mark. It's quite fascinating, especially if you haven't done much wrenching on modern CANBUS-controlled cars.

Basically, we get to see that the technician was able to pin down the problem via computer diagnosis. Noticing everything on the vehicle's medium-speed computer network (used for its medium-priority functions) was acting up, he figured out that the safety systems built into the truck's taillights on the same network had burned out, causing the cascade of malfunctions that were apparent in the cab.

Water had gotten into the taillights and fried some modules in the blind-spot and cross-traffic monitoring systems, wreaking havoc on the truck's computer network that manifested itself as a dead dash panel and unresponsive safety alerts.

Makuloco's explanation seemed pretty clear, and it didn't look like he even had to spend all that much time diagnosing the problem. So how the heck did we land at a $5,600 repair bill?

Well, one of these taillights alone lists for over $1,000, and that doesn't include the modules needed to run the Limited's safety features. Once you add up all the connected parts that needed replacing and tally up labor costs, you pass $5,000. Unreal, and yet, not all that surprising. Complicated, networked parts are expensive to replace. It's logical when you think of it that way, though "$5,600 taillight replacement on an F-150" is not a phrase I would have imagined writing 10 years ago.

This page from Ford's parts catalog shows some of the tech inside a 2018 F-150 Limited's taillight.
This page from Ford's parts catalog shows some of the tech inside a 2018 F-150 Limited's taillight.

It seems the unlucky owner of the 2018 pickup in this video (which showed about 95,000 miles) is far from the only person who's dealt with such an issue in one of these trucks. This F150 Forum thread alone documents a decent handful. I peered through Ford's technical service bulletin library (also available on F150 Forum) and couldn't quickly find anything pointing to this as a common problem, but I dropped Ford's PR representatives a note asking if they had any insight. I'll update the post if they expand our knowledge on the subject.

If you're looking at buying a vehicle like this, new or used, it's definitely prudent to investigate what some of these parts cost and consider reliability. Maybe even see if you can get insurance against such situations. As for F-150 owners, the taillight for lower-spec trucks without radar systems, and with good old-fashioned incandescent bulbs, lists for a much more reasonable price of about $250.

If you do break a light on a high-trim truck and can't stomach the four-figure replacement cost, I guess you could run a non-sensor light and sacrifice your sweet safety features. Then again, you'd still have a network disruption on your hands and perhaps cause yourself even more grief. The only real solution is to opt for a lower trim level, or a more primitive truck.