Maybe it would help the experts if you could remind them of the problem ?
It can be a pain to have to trawl back through a long threadā¦
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As I said, I wasnāt criticising - its just it seems markedly quieter on the forums these days.
Iāve also posted seperate topics in the electrical section of the site.
Like I said, no judging or criticism from me; if anyting I was just surprised. I much prefer using a forum to social media, but maybe thats the way things are going.
And with regards to reposting the problem, it was only 7 posts and 2 days ago 
But I shall!
Iām reposting the video as suggested:
Iāve swapped the looms again, checked grounds, checked fuses.
Because both looms display EXACTLY the same symptoms it must be something to do with the wiring left on the car. The only modifications or adjustments iāve made to the car since it was all working:
- Removed original ECU
- Removed dashboard and all electronics
- Removed engine and therefore disconnected everything that attached to that
- Removed front bumper and disconnected horn etc
- Removed gearbox and electrical connections
Some thoughts (and iām not even a novice, more of a nov)
The ECU is unlikely to be the issue as the rocketter uses a different ECU anyway. The Gearbox wires have been attached and not attached with the same result. The engine connections are mostly disused in the Rocketter conversion for obvious reasons.
So this only leaves the dashboard.
The main dash with the speedo and stuff only uses two connectors which canāt be fitted in the wrong way.
I removed the immobiliser, but as the ECU has been removed that was attached to that immobiliser, that wont be the problem.
The fact that the wiper seem to control the power to the car and the fact that the cars becomes āpoweredā when the battery is connected are the stand out symptoms.
I would have suggested the ignition switch, but does the ignition switch stop power from the battery when the battery is connected, unless the key is in the correct position? Either way, that wouldnāt explain the windscreen wiper controlling power to the car.
Andrew, when you say youāve replaced the āloomā which part of the loom do you mean? are you including the entire fusebox, under dash sections that are attached onto the re-enforcement bar, the rear car loom that goes back to the lights, battery etc. engine bay loom, or just one / some of these.
Carl - sorry if it wasnāt clear, it gives you an idea of the clairty of my mind with these things!
Iāve swapped out the main loom that runs from the battery to the engine (including the main fuse/relay box).
Andrew
My limited understanding suggests that the ignition switch should be stopping the flow of current to the rest ot the car from the battery? So I should change that and see if anything changes.
I canāt believe you have done, or if it would even be possible or what symptoms it would give but you havenāt connected the ignition switch connector to the wiper switch have you? From memory they are both 6 pin plugs.
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Thanks Robbie!
I donāt remember them being the same - I thought one was an 8-pin connector with one pin missing, but I might be remembering wrong!
Whilst it seems highly unlikely, for reasons I wont go in to here, I do do (I said do do!) stupid and unfathomable things from time to time.
Iām not at home today so I canāt go and look. I found this picture on the IL Motorsports website, so i was semi right - one of the connectors has a pin missing, so for me to connect those incorrectly would take superhuman effort but you never know!
Even if it isnāt that, I think yourāe on the right lines - its got to be to do with igntion and/or windscreen wipers.
Although, having said the above - I wouldnāt have been able to see the back of the steering connectors very easily so that would explain somewhat how I found it possible!
Thanks Robbie - is that for an NA? ALso what book is that in? Iāve got the individual diagrams of the wiring systems but that looks great!
Oooh porn indeed! Mineās a Eunos so there might be subtle differences - need to find myself one of those though.
I find that the Roadster & MX-5 wiring tends to be very similar.
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Thanks very much for your help. When I get home iāll check those connectors. Fingers crossedā¦
Lots of the car is āHot at all timesā including things like Lights, and Room fuse and Fuel Injector fuse etc
What Robbie has said above while I was slowly checking things makes a lot of good sense.
āHot in Run, or Startā comes from the ignition switch.
It should enable the Main Relay in the engine compartment supplying 12V to the fuel pump relay (which has a switched ground as well with various safety interlocks, varies with auto or manual).
It should enable 12V to the ignition coils (I assume you take this to the jag coil system instead?)
It should enable 12V to the Meter fuse and Engine fuse, going to injectors etc.
I donāt see as you need anything else just to get the jag engine gong with its ECU. All the rest of the stuff including charging etc is extra.
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Rebecca my ever patient (and honest) fiancĆ©e said āare you going to tell them? Donāt tell them!ā
Can you see where this is going?
It wasnāt the ignition and wiper that Iād swapped, there was another combination switch on there that was a 6 pin connector 
Having searched google to check I was an absolute melon, it seems nobody else in the world has managed this. Sorry all, I was so stupid.
Thanks for all your help, patience and electronic mastery - social thanks to Roadster Robbie in that regard.
Anyway, as soon as I switched those, I reconnected the battery, the key now works, as does the heater and the windscreen wipers!
Iām off to ask myself some pretty searching questions and drink wine.
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the important thing is you have fixed it so can carry on! (oh and drink wine)
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