Why are you gauges going to 0 after it's started. Already replaced alternator bterminals

Hi, this is Bo, an auto expert on RepairPal's Car Genius team! When all your gauges, windows, and other electrics go out after starting your 2005 Mercury Mariner, it feels like electrical gremlins at play. But don’t worry, it’s more likely a power distribution issue. Since you've already swapped the alternator, battery, and terminals, I'd check for a loose or corroded ground connection, especially the main chassis ground. Another suspect could be the ignition switch, which may not be sending power to the accessories once the engine is running. If the problem persists, a relay or fuse box issue could be the culprit—worth a look! If you need any further advice or want help finding a trusted RepairPal shop in your area, please feel free to call us at 877-913-1554!