VACUUM LINE DIAGRAM MAZDA MIATA - 1993 Mazda MX-5

Question edited for clarity.
Question moved to model category.

Yes, you are correct, disconnecting the fuse box has broken the pairing between the key and the immobilizer system. Did you remove the main connection plugs to the fuse box? My thought is that those connectors have never been removed since the car was built and breaking a remaking the connection, you might have some connections that as not as good as they should be. Pull the connectors again and give them a good spray with electrical contact cleaner (that is NOT WD40). Then reconnect.

There is various ideas on resetting the Immobilizer here.

https://www.google.com/search?q=mazda+miata+immobilizer+system+reset

Or a Mobile Auto Locksmith

https://www.google.com/search?q=mobile+auto+locksmith+near+me

Just for fun, here are the Fuse Box locations and diagrams. They have changed over the years, and as you didn't state the year, here is all of them.

Mazda MX-5 Miata (NA; 1989-1997) fuses

Fuse Box Diagrams https://fuse-box.info > mazda > mazda-mx-5-miata-na...

Here you will find fuse box diagrams of Mazda MX-5 Miata 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, get information about the location of the fuse ...

Mazda MX-5 Miata (ND; 2016-2023) fuses

Fuse Box Diagrams https://fuse-box.info > mazda > mazda-mx-5-miata-nd...

Fuse box diagram (location and assignment of electrical fuses) for Mazda MX-5 Miata (MX5) (ND; 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023).

This is a useful wiring diagram. I would say try swapping the relays over first and see if Low Beams now work and High Beams don't.

Other possibilities are two failed bulbs, or a broken connector. A good test meter should be able to trace this.

https://boostedmedia.net/automotive/videos/tech-videos/mx5-miata-headlight-wiring/


It does appear to be a known issue

https://www.google.com/search?q=2013+mazda+miata+no+low+beam+headlight

This suggests the combination switch

https://forum.miata.net/vb/showthread.php?t=531436

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1-3-4-2. You can find other specs at https://mossmiata.com/miata-1993.

most are vacuum operated, maybe a broken, leaking or clogged vacuum line. If electric maybe a corroded or broke wire.

Maybe you can find it with the wiring diagram.
http://www.mellens.net/mazda/mazda_miata_extra_manual/1996_wiring.pdf

Most often the main 80 amp fuse is blown - happens when someone slips with a socket extension when trying to remove the battery terminals. Fuse is under the hood, passenger side and here's a diagram: http://www.mellens.net/mazda/Mazda-Miata-1997/fuses.pdf

For 1991 Mazda MX-5 Miata 1.6 liter DOHC L4 B6 check...



Hope helped (remember comment and rated this).

Things that make your engine do what it is doing.

1. Vacuum leak
2. EGR valve

Find the vacuum leak if there is one.. and check the function of your EGR valve.

A functioning EGR valve with an ORAL vacuum line suction test will cause the engine to stall / die when suction is applied to the ORAL external line.

Even if it passes the ORAL test... it can still have carbon build inside the plumbing that does not allow the seating pin to fully seat and the engine will surge or be hard to start when warm.

So check / listen carefully for vacuum leaks and check the EGR valve.

THERE IS A VALVE ON THE RIGHT SIDE OF THE INTAKE MANIFOLD THAT OPEN THE RUNNER.IT HAS A VACUUM LINE TO IT.FOR IT TO BE STUCK OPEN EITHER THE SOLENOID IS BAD,THE VACUUM LINE IS BAD OR THE RUNNER IS GUMMED UP WITH CARBON AND STUCK OPEN

Mazda Miata/MX5 Service and Repair Manuals is good for this kind of thing, has all Miata manuals ever.