miataa

I recently installed an MTX-L and an MS3X and I wasn't able to get the car to idle. Through testing I was making progress until I had intermittent starting problems. The car would decide when it wanted to start. It would either start like normal, or do absolutely nothing, no crank, no attempt to turn over, no click, nothing.

So when I turned the key the "on" position, everything comes on fine, when I turn the key to "Start" my radio turns itself off, while my AFR gauge stays lit. When I press my push button start nothing happens at all. When I am outside the car with the headlights on and the key is turned to "Start" the headlights stay on, and they don't dim, or flicker, or budge at all. So I figured it was the starter. Long story short, I have replaced the starter, battery, and battery terminals. When I went to check my ignition switch I noticed something that seemed odd, and maybe the reason I cannot start my car. It looks like the connector has been damaged, melted even. Is my switch bad? Could my switch be causing excess heat that could melt the plastic in the connector?

Can someone help me figure out this problem? Thanks!

Does this look like my switch is bad? You can see damage on the bottom of the connector

Here is a close up of what looks like melted plastic

This area circled in red is discolored and looks melted

top view of damaged area

Does this switch look like it needs to be replaced?

Here you can clearly see where the middle divider melted away. Could this have been caused by the switch being faulty?

miataa

Here is a picture of my switch. Is it possible that this looks dirty enough to cause a draw large enough to melt the connector?

bjorno

Have you wired up anything to the same circuit as the switch? (switched power for the 02 sensor heater element?)

miataa

Nope. I installed the ECU and spliced the MTX-L into the ECU's harness. Nothing crazy.

I'm definitely curious if something is causing a power draw or if the switch just went bad and the bad switch caused the melting of the connector.

NBoost

Though it happened after you installed your MS3x, I would suspect this mod to cause something of this nature. That connector is definitely melted, and definitely had more current flowing through it than you want, for a longer duration.
Maybe an effect from holding the push button start for longer than normal in an attempt to get the car to start? I would check your install of the push button, and put a fuse in it.

If all that checks out, then look to the MS3x. I just don't see it as a plausible "first place" to check, when you have a push button start mod in the mix.

miataa

Thank makes a lot more sense to me than the ECU having anything to do with the problem. I ordered a new ignition switch. Do you think it's safe to try and use the old melted connector?

I was thinking that if I can't use the old connector, I could cut it off and make individual connectors on the ends of each loose wire and hook them up appropriately to the switch. Could there have been damage to the wire itself?

NBoost

New switches aren't cheap, and you already bought one. Interior fires aren't cheap either. So no, I would source a good condition connector from another car. Splice it into the wiring properly, and then proceed.

I don't advise connecting the ignition switch in any other way than the factory connector. Its just simpler/easier that way.

rleete

iTrader: (21)

The switches themselves are fairly easy to pop apart and clean. Open it up (careful not to lose the tiny springs), clean it out, and refill it with dielectric grease.

That will also tell you if the contacts inside are burned, or if the problem lies elsewhere. I suspect that Nboost is correct in that it's more related to the push button than the switch.