Heard a senior tech say check grounds first, saved me 3 hours

Last month I was chasing a Garmin 430 that kept losing power randomly. I spent a day swapping trays and connectors before I overheard a guy with 30 years in the Navy say "always check the ground strap before touching anything." Sure enough, the strap at the back of the rack had a hairline crack I couldn't see. Now I start every intermittent power issue by wiggling that ground. Anyone else have a simple fix that took way too long to learn?

3 comments

3 Comments

felixm2919h ago

Haven't you ever seen a ground strap fail that looked perfectly fine?

amy_martin13h ago

Watch that strap wiggle when you load the system up, not just when it's sitting cold. Did you check it with a clamp meter under full draw to see if the resistance jumps when it's carrying current? Strap might look fine but turn into a resistor once the amps start flowing.

the_oliver6h ago

Dude you're totally right... I had a battery ground strap on an old Ford van that looked brand new, no cracks or corrosion at all. But under a full alternator load it started getting warm to the touch and the voltage meter was all over the place. Put a clamp meter on it and the resistance just kept climbing as the system warmed up... turned out the crimp inside the terminal was loose from the factory. Replaced it with a simple piece of welding cable and never had another voltage drop issue again.