Mazda MX-5 Miata banner
1 - 19 of 19 Posts

·
Registered
Joined
·
199 Posts
Discussion Starter · #1 ·
Hi all,

My first post here for a long time, although like many before me, i've been lurking.

So, to make the bloody long story as short as possible, here goes in the form of a list:

Bought 1991 Eunos Auto to do Rocketter conversion
Installed Engine and MANUAL gearbox and all other mechanical components
Got to the electrics, wired in the new ECU, fitted a loom from a manual car, and then haywire. Ha.

Haywire is as follows:

Connect battery cables
Fuel pump, BRAKE light on dash lights and various relays click, all WITHOUT the key.
Key doesn't do anything.
Moving the wiper stalk down cuts power but does nothnig with the windscreen wipers.
Headlights, rear lights, number plate lights and side lights all work.
Headlight retractor doesn't.
Don't seem to be getting any power to MAIN fuse (or is it a relay?), but that was also the same with the auto loom - so unlikely to be the main fuse.
I've checked all fuses, the only blown one is one for the aircon fan which ive removed anyway.



Heres a short video showing the above:

flic.kr/p/2mmd2ip

Not to put too finer point on it, but I wish i'd never bothered!
 

·
Happily expanding the To Do list since 1997
Joined
·
10,551 Posts
Not sure if it'll help or just open a fresh can of worms but there are Roadster wiring diagrams here, though they're in Japanese: EunosRoadster配線図 (do-da.co.jp)

As they have sets of drawings called NA6-1 and NA6-2 it looks as if there are two generations of wiring for Mk.1 1.6 Roadsters. If you think it might help, I think I have a crib sheet somewhere listing Japanese characters for various colours.

<edit> Here it is:
 

·
Registered
Joined
·
2,423 Posts
Forgive me if wrong?? But you got a red fuse wire coming off the negative post of battery..you sure you got polarity right?


Sent from my SM-N950F using Tapatalk
 

·
Registered
Joined
·
284 Posts
I think progress has been made, he's swapped the plugs on column... more info on MX5OC forum
"It wasn’t the ignition and wiper that I’d swapped, there was another combination switch on there that was a 6 pin connector"
 

·
layabout
Joined
·
2,352 Posts

·
Registered
Joined
·
284 Posts
Well I can understand that, I think it was a desperate situation! ;) I wouldn't like to tackle that loom swap!
 

·
layabout
Joined
·
2,352 Posts
I wouldn't like to tackle that loom swap!
It's not that bad as looms go, most of an Mx5 is laid-out in an order & the various looms overlay the components / connectors...

except the possible 2 similar plugs / sockets on the column stalks 🤭

Rich.
 

·
Registered
Joined
·
2,423 Posts
Thats defo 1 to remember. So he put the 6 pin ignition plug on the wiper stalk?

Sent from my SM-N950F using Tapatalk
 

·
layabout
Joined
·
2,352 Posts
Thats defo 1 to remember. So he put the 6 pin ignition plug on the wiper stalk?
seems that way 😲

although this does supply usefull info so heres some photo's if anyone searches in the future....


rear of stalks....


4 plugs connect, one of the two 6pin plugs & sockets are only populated with 5 wires / terminals


this shows the ignition-wiring plug in the stalks (top left) - has 6 wires in the plug...


ignition plug on left (6 terminals) all 3 plugs are interchangable....

Rich.
 

·
Registered
Joined
·
2,423 Posts
Funky times lol.. ive just chased my tail for an hour on wiring too. My boost soleniod always clicked as it was cycling when ignition on..i cut the tesa tape off and redone some connections to determine that it wasnt getting neg trigger from ecu... quick text to mapper and last mapping session he said he changed it to only output with revs...pheww gotta have my hi boost. And glad he answered on a sunday else id have laptop out and probably introduce more faults

Sent from my SM-N950F using Tapatalk
 

·
Registered
Joined
·
199 Posts
Discussion Starter · #13 ·
Sorry guys, I didn't keep up with the notifications!

haha, yes all very embarassing..!

Anyway, things have progressed now, i've got power everywhere, i've connected all the connectors in the right place (!) but now I am faced with the starter motor solenoid not getting power.

My car was originally an auto, so had a form of inhibitor switch which I thought i'd bypassed by bridging the connection between black/blue and black/red. However, i'm getting no measurable voltage at either the ST Sign Fuse, the wires themselves after the main fuse or the wires from the ignition connector.

My undersrtanding is that the solenoid wire should power when then key is turned to start, but that is not happening for me.

Could it be something to do with the inhibitor switch or lack thereof?

Sorry for posting everywhere! Suffering with anxiety and doing a Rocketeer build do not make good bed buddies!
 

·
Registered
Joined
·
199 Posts
Discussion Starter · #15 ·
It's an MBE ECU, the instructions don't mention having to do that and no other members have mentioned it so I guess we don't need to do that.

It's a weird one - the starter spins if I test it with direct voltage from the battery, when the car is wired up its getting voltage. So it's almost definitely to do with the solenoid wiring.
 

·
Registered
Joined
·
199 Posts
Discussion Starter · #16 ·
Although, giving it more thought (I barely think about anything else!) it could be the ignition switch itself. The solenoid wires should be getting power when the key is turned to start and they aren't.
 

·
layabout
Joined
·
2,352 Posts
Although, giving it more thought (I barely think about anything else!) it could be the ignition switch itself. The solenoid wires should be getting power when the key is turned to start and they aren't.
disconnect the ignition switch wiring plug and do a continuity test (or feed +12v directly into the starter-activator wire)

both will tell you if there’s a wiring problem (direct power will be an acoustic test!)

the ignition switches are dismantlable so the contacts can be cleaned…

I’ll get a photo of that wiring connector you were asking about on Fb shortly…

Rich.
 

·
Registered
Joined
·
199 Posts
Discussion Starter · #18 ·
Thanks Zed, I worked out that wiring connector!

My loom has been messed with previously which is not aiding my mission! That connector connected to a male instrument cluster connector that was the wrong type on my loom.

I tested voltage at the black/blue wire at the ignition switch yesterday (I think - one probe on the wire and one connected to ground or did I get the ground bit wrong?) and there was no voltage when the key was turned in any position.
 

·
Registered
Joined
·
199 Posts
Discussion Starter · #19 ·
Johnson, I found the tunnel! (obscure reference for you)

It was my ancient immobiliser.

It had been spliced in to the black/blue wire which goes via the main fuse block to the alternator and then hidden under some tape. Reqired the connection and bravo, power to the starter. Doesn't fully turn though, but thats (another) seperate problem!

Thanks again for your help :)
 
1 - 19 of 19 Posts
Top