2005 Mercury Mariner 187000 miles
Been having this issue for a while and it's gradually gotten worse. It won't start at the first key turn, I'll have to jiggle and jiggle to get it to finally start. Dash lights do turn on at axillary, and the radio will pause when I try to start it like normal, but all I get is a single click noise coming from under the radio. I also get a soft electric hum that can be heard in the engine bay, coming from the firewall when the key is turned all the way. I changed starters multiple times, and it'll behave a little better right after but always goes back to the same issue. I've changed the ignition assembly and the switch, and even the switch plug itself. Now it won't start at all, any ideas? I'll try just about anything at this point.
Devin from United States
2 years ago DE

I had to go to the junkyard to get a whole ignition assembly, and it came with a black box ringed around the key part of the ignition. I assumed it was the key reader, took it off and kept mine, but no luck. For shits and giggles i put the junkyard key reader in (I changed the key cylinder to my key) used my key, and it works just fine. It's been over a month now with no problems.