Please Help! 2018 Mazda3 won’t start after being re-keyed with new fuel pump and starter relays

[KillerBeevz]

Hi guys new here to this community and need help fast please

Just got a 2018 Mazda 3 and it came with only one key fob that was broken to bits and naturally missing the actual chip so I had it rekeyed yesterday only to find it still wouldn’t start. Upon further inspection both the fuel pump and starter relays were missing…replaced them both and still having the same problem. I’m thinking maybe I need to reset the ECU? What’s the reset sequence on this year? I can’t find anything online for this specific year on the ECU reset sequence. Please help!? Also worth mentioning my brother is who acquired the relays so I’m not super confident he got the correct ones.

 

[negusm]

Define..."won't start"? When you turn the key, what happens? Do you hear a click? Does the engine turn over but not fire up?

Honestly between the security setups in modern cars and all the electronics between the key and the starter, you may need to take it to a dealer to get it sorted.

 

[KillerBeevz]

Define..."won't start"? When you turn the key, what happens? Do you hear a click? Does the engine turn over but not fire up?

Honestly between the security setups in modern cars and all the electronics between the key and the starter, you may need to take it to a dealer to get it sorted.

It’s a push start I’ll add a video to show you what it’s doing. Turns out my brother mixed up the relays and now I can’t find a diagram to get them in the right locations. Owners manual only has the fuses listed not the relays and I cant find one online either.