2007 Miata - No power to center console

[green walrus]

I bought a 2007 Miata whose previous owner had completely stripped the interior to turn it into a track car, but they never took it on the track. HVAC, airbags, and steering wheel. Everything was gone.

I have nearly the entire dash put together from mostly salvaged parts from pick-n-pull and Facebook Marketplace.

My problem now is that nothing in the center console works. The hazard light switch doesn't work (blinkers work, as well as the passenger airbag light), the climate controls don't work (no lights, dials do nothing), and the 12v outlet has no power. There is no radio unit currently installed.

I checked the fuses in the engine bay and the interior panel, and they're all in good condition.

My first thought is I'm missing some ground connections somewhere, but I don't know where to look. Any other suggestions of where to start would be appreciated.

2007 Miata - No power to center console

[nimble cypress]

look along the metal behind the dash where the radio/HVAC sit.
there should be a bare metal bolt where a ring terminal should bolt down. if you don’t see anything check HVAC metal box frame, metal brace center under radio area and the side frame panels near footwells. if you find a “loose black wire with a ring,” then that’s your missing ground.

Another thing to check is behind the radio. it could be missing the radio harness jumper. miatas route some power through the radio harness jumper. if the previous owner ripped the stereo wiring, and the connector for the factory head unit is unplugged or missing, certain circuits (including illumination power, constant power, ignition accessory power) might be broken. look behind where the radio would be.
is the big white stereo plug just dangling there? is it unplugged? broken? missing? if so, that could be partly why the 12v plug and climate control lights aren’t working.

a blown hidden fuse or link may be the case. miatas also use fusible links and hidden relay fuses under the hood. a blown fusible link could kill power to a whole section. check underhood fuse box for “ROOM” or “INTERIOR” fuses. look for any 20A/30A block fuses, not just the blade fuses.

an HVAC specific connecter could be missing. the HVAC panel (temp, fan speed, etc.) has its own separate plug.
if that plug behind the center stack isn’t connected, it won’t light up or function at all. it’s a medium-size rectangular connector, though not the same one as the radio. double check if the HVAC harness connector is plugged in properly.
sometimes people just shove the dash back without reconnecting all the plugs

[green walrus]

I'll take a look for those grounding wires. Hoping I don't have to remove anything to try to find them though.

The connectors for the radio and HVAC are intact. The HVAC is plugged in. The radio is loose.

I'll double check the block fuses but they seemed ok.

[nimble cypress]

that seems like it’s missing ground or missing accessory/illumination power. both of which could easily happen if the ground ring terminal behind the dash is still loose. you probably won’t have to remove much unless the previous owner tucked the ground wire deep.
most Miata NC grounds are just behind or below the HVAC/radio area. you should be able to see them just by peeking up behind the radio hole with a flashlight. look for bare metal bolts sticking out of the frame, a black wire or wires with metal ring terminals not bolted to anything, or even just a ground bolt with nothing on it.

if you want to be 100% sure it’s a ground problem even without finding the wire, you can test by clipping a wire from the metal HVAC box to the negative battery terminal. the see if your 12V outlet or hazards suddenly work

[green walrus]

I couldn't find any ring terminals but I found this. There's another that's fastened near the passenger kick panel. Is this a ground wire of some kind?

[nimble cypress]

sorry for my late reply, been playing drums.

the plug you found in your photo is 100% a ground distribution connector. that’s called a ground junction block. all those black wires bundled into that connector are grounds for multiple systems: HVAC, 12V outlet, radio, hazard switch, etc. that block normally plugs into a metal tab or bracket that’s bolted directly to the chassis, or it screws into the car body as its ground point. that is why your entire center console isn’t working. either find where it originally clipped in (should be a metal prong or bolt tab near the glovebox or center console). or just bolt a ring terminal to it and screw it directly to clean bare metal anywhere close by

[green walrus]

I'll take another look. If I can't find the connection, what would be the best way of connecting this to a ring terminal?

[nimble cypress]

i think it would be to strip one of the wires (maybe 1/4 inch of insulation) coming out of that big white connector and then pick any of the black wires—they’re are all grounds and are tied together internally. use a wire stripper or gently with a blade if you have to.
then crimp on a ring terminal sized for the bolt or screw you’re going to use. use a proper crimp tool if you have one (not pliers, unless you’re desperate). if you want it to look extra good, add a little solder into the crimp after. bolt the ring terminal to a good piece of chassis or metal dash frame, then sand off any paint where you’re going to bolt it—bare metal only. use a self-tapping screw or an existing bolt. tighten it firmly so the ring terminal is locked down. lastly wrap the exposed connection lightly with electrical tape if you want extra protection

[green walrus]

That's probably what I would've done. Just good to have a 2nd opinion. I gotta go buy some of those grounding terminals before I can try anything. Thanks for your help

[nimble cypress]

no problem!

[green walrus]

Finished the wiring. Everything seems to be working now