I Ordered 47 Garmin Dash Cams and Skipped the OBD2 Scanner Pending-Codes Check. It Cost Me $3,800.

Last September, I signed a purchase order for 47 Garmin dash cams. It looked like a no-brainer. A fleet customer wanted the install done before the end of the month, the models were ones we'd handled a hundred times, and my margin math already looked good. By the following Friday, I was standing in our shop with six dead vans, one annoyed marine dealer, and a return label that made my stomach drop.

I'm the operations guy for a commercial vehicle electronics outfitter. I've been ordering Garmin products and handling installs for six years. In that time, I've made and documented seven significant mistakes, totaling roughly $18,000 in wasted budget. This one was mistake number six. The painful part is I knew better.

Back in my first year, I made the classic specification error—assumed "standard" meant the same thing to every vendor. Cost me a $600 redo. This was the same overconfidence, scaled to 47 units.

If you work this side of the industry, you know the routine. A customer asks "what is the best dash cam for a car?" and you answer: for most cars, a Garmin Dash Cam 67W. For smaller cabins, a Garmin Mini 3. The hardware is rarely the hard part. The hard part is the 12-volt system behind the dash. I forgot that.

The P.O. That Started the Problem

The order was 30 Garmin Dash Cam 67W units and 17 Garmin Mini 3 units. Then the customer tacked on a marine dealer's request: two Garmin chartplotters and one Garmin Quatix 8 marine GPS smartwatch for the demo counter. I combined everything into a single purchase order to save freight. That part was fine. The mistake was treating every line item like we'd already installed it twice.

I was in a hurry. The fleet job had a hard deadline. The shop was stacked, so I gave the P.O. one quick glance and approved it.

Honestly, the second I hit "approve," I had that sick feeling. What if the Quatix 8 didn't use the same charging cable as the Quatix 7? I pushed it away. That's the part I hate admitting.

Where I Cut Corners

Our normal batch-install process has three pre-install checks:

1. Bench-test every unit before it goes near a windshield. We use an EcoFlow Delta 3 power station for this. It gives us clean, stable power and lets us simulate parking mode without draining a customer's battery.
2. Run the OBD2 scanner pending codes check on every vehicle. We log battery voltage and look for anything the ECU isn't happy about. If a vehicle has a pending code, we find out before wiring anything into the OBD-II port.
3. Verify accessory compatibility for anything that isn't a standard dash cam.

I skipped steps one and three. I probably would have skipped step two too, if the van hadn't refused to start.

The "just plug it into the OBD port" thinking comes from the early dash cam era, before parking mode existed. That's changed. So has the electrical load.

Here's something vendors won't tell you: a rush order doesn't mean the rules change. It means you do the same checks, just faster. I did the opposite.

The Calls All Came on the Same Morning

The first call was the fleet dispatcher. "Van 14 won't crank." I thought it was a fluke. Then van 8. Then van 22. By noon, six vehicles had drained batteries and a fleet manager was asking who was going to explain it to their safety director.

We pulled one of the Garmin dash cams and checked the wiring. It was clean. To be fair, the Garmin hardware gave us zero trouble. The failures were on my side. When our install tech finally ran the OBD2 scanner, it showed pending codes on two of those vans. One had a BCM communication fault. Another had a steering angle sensor code that hadn't turned on the check-engine light but was still living in the background. Those two, plus the other four, all had weak batteries. Skipping the pre-scan turned a two-day install into a six-week headache.

And the marine dealer wasn't happy either. The Garmin Quatix 8 marine GPS smartwatch itself was beautiful—that solid, salt-ready feel. But I'd ordered the watch-only SKU. No charging cable, no spare band. He had cleared a demo case for "the new arrival." I had arrived with half the product.

What the Rework Cost

Let's do the math. That week cost us about $3,800 in labor, replacement batteries, shipping, and one very expensive expedited cable. Don't hold me to the exact number; my spreadsheet got ugly after the second invoice. But that's the right ballpark.

The cost of doing each pre-install check? Rounded up, about four hours of shop time. I could have hired a temp to run the checks for one-fifth of the rework bill.

That's the prevention-versus-cure thing, right? Prevention is boring. It doesn't make a good story. Cure is the story I'm telling you now.

The Checklist I Use Now

Since that week, the checklist is non-negotiable. We still sell and install Garmin products because they keep working when other stuff doesn't. The Garmin Quatix 8 marine GPS smartwatch is now one of our top marine accessories. But we don't touch a vehicle before these four things happen:

• Bench test every unit. We still use the EcoFlow Delta 3 power station. Yes, it's overkill for one camera. For 47, it's exactly right.
• Scan before any electrical tap. OBD2 scanner pending codes, battery health, ground integrity. Five minutes per vehicle. Worth every second.
• Check SKU details. Watch-only versus bundle. Cable included. Band size. Small differences are where money goes to die.
• Question your own certainty. If I'm sure about something, I try to prove it wrong. That habit alone has caught more mistakes than I want to count.

So what is the best dash cam for a car? In this shop, the answer is still a Garmin—a Dash Cam 67W for most cars, or a Mini 3 if you want something small. But the best dash cam in the world won't fix a skipped pre-install check. It'll just sit there, recording your mistake in 4K.

If you're about to order a batch of gear, build the checklist before you build the purchase order. The hardware will be fine. The process is what needs the attention.