2005 Mazda 626 (won't start)

Maintenance/Repairs
1

my sis-in-law has this mazda that won’t start. the other morning she went to start it up and the starter just clicked rapidly, indicating dead battery. So her dad tries his battery out of his 1994 Ford Ranger, only when he tries to hook it up, the horn blares incessantly. so he went and bought the correct battery for it.
now, when you turn the key, the dash lights come on normally, but when you turn key all the way to start position, nothing happens, no lights go out and come on as I am used to seeing in other vehicles at start up.

HERE’S WHERE I AM STUMPED: the power locks don’t work, the dash lights don’t work, the taillights don’t work. windows go up and down and headlights come on and go bright, blinkers work, everything else works except aforementioned items.

I want your guesses or expertise. I am wondering about ignition, ignition relay, or starter relay. I did swap out good relays for the starter relay and nothing.

Help me help her help get my car back. :slight_smile: [she’s currently using my car]

2

Did dad hook the battery up backwards. A battery is a battery. Manufactures lay out the positive and ground posts differently depending on the model of car, but they are all 12 volts. I would look at fuses first. The lights should go out unless there is a fault. This could be a smoked computer.

3

ok. if it is a smoked computer (you’re validating my wife) how big of a job is that or what does that entail?

4

Sounds like a bad relay to the starter. If the relay was working the dashlights radio etc would be cut off temporarily for starting. The next issue is a bad ignition keyswitch or connectors that fail to turn on the right circuits for starting. Work on this angle before more complicated theories, Been there and the results taught me to be simple in my approach not complicated. Good luck.