Ignition switch..issues
 

Hi
I have an aftermarket ignition switch.
Marked at the rear start... ign ..batt..acc
Unfortunatly I had a separate issue which meant I had to remove the wires to the switch.
On reconnecting back up I am confident I have the wires backing correctly barring the wires ( 2x joined wires one obviously makes the ignition warning light function)that go to the charging system. Where on the starter switch should they go? On the spare ignition terminal?

My understanding of the switch labels is

Start - goes to starter solenoid

Ign - goes to ignition system

Batt - power coming from the battery to the switch

Acc - is the accessory function - so you can "do one click" and then switch on the radio for example

#######

Looking at my PV wiring diagram (for example) the wiring suggests that the ignition switch has to cope with a lot of current - this is not the way many more modern vehicles are wired. (especially as more modern vehicles use more elctrical items than the PV!)

I think you need to make sure the aftermarket switch is "man enough" for the job it is being asked to do. That may or may not be the case...

[EDIT]

Forget to say it is possible that the alternator / dynamo low charging warning light operates independently from the ignition switch - depending on the wiring diagram / what has been fitted - it is usually just coming from an alternator as things get thought about at the alternator / rectifier for more modern vehicles

Thanks, confirms I have it correct.. the switch has been operating well for a number of years..it was me causing the issues by removing the wires and forgetting to note their orientation. Still confounded as to where the wire I described goes

Your descripton of the wire which is joined - one part of which goes to the charging light - sounds like an aftermarket fix to me. I could be wrong but...

...I get the feeling your vehicle has an electrical system that is part factory, part adapted, part goodness knows what.

For the charging light situation I suggest you start with the alternator and see what it is meant to do. How many wires / plugs are on the alternator?

On some vehicles I've seen people try to wire a modern alternator to an external voltage regulator that was previously used for a dynamo - mixing up systems - just trying to get something to run. You get things unplugged or taped up or spliced and it quickly ends up looking like a rats nest.

I sympathise with the feeling that everything was OK before it was unplugged but this may or may not be the case. I think it is prudent to do a bit more checking.

It's always a good idea to photograph every thing before disconnecting or removing. that way you always have a record as to how it goes back

Clive;

Typically, AMP Indicator has Ignition Power on one side, and it runs off to the Alt, where is powers the Field, OR gets pulled to chassis when Alt is not putting out, which puts voltage across indicator and lights it...if your wiring is not factory, but "customized" I'd triple check it to be certain.

Reference: https://www.sw-em.com/123GT_Charging_System_Notes.htm

Good Hunting!

Firstly thank you for all your advice and help

My car has been modified and sadly I did not have the time to photo anything as it was an accident that caused the wires to become detached thanks to my ape like hands.
My car has a dynamo and no alternator. The two white wires track back to the fuse box area and alternator ign warning light.
As a precaution I will fit to the acc terminal..I will then turn up the juice and see what shakes loose. Should know this but sadly I cannot remember it..

Ron: Dynamo not Alternator.

Clive, is your car starting and running?

Was there a recent thread about using an MGB switch on this forum? That had diagrams.

Clive;

For 1800 with Dynamo (thanks for clarifying, Derek!), wiring and function of Chg Ind are actually very similar, but specifics at Chg Sys are a bit different due to it being Dynamo based.

Two white wires should be connected to (Ign Pwr) terminal of Ign Sw, heavy gauge one supplies Fuse 2, and light gauge supplies Chg Ind (and on the other side of indicator, wire changes color to Brn-Yel and goes to Vreg D+ to sense Dynamo output).

Reference: https://www.sw-em.com/1800_Wiring_Di..._No_10000+.jpg

Cheers

Thanks Derek and Ron

In short no it did not start ..but I have tracked it down to the ignition module (points replaced by electronic some years ago) as I have no spark at the king lead. All other wires to and from the coil have been traced and checked and OK. Also I have a brand new spare coil which I used to ensure the extant one was good. It seems that when I was arseing around with the car I probably shorted out the module somehow

I have a spare dizzy with points and what have you so I can shove that on until I get a new mosule (on its way)

Ron...Turning to the white wires..I can shove them to the positon on the switch marked IGN where the wire to the coil is; is this the terminal you are referring to ? . I was going to put it on one of the ACC terminals as I guessed it does not matter where it goes as long as its on the switched side and getting power....

Iam going to have a go at starting it and putting it back to normal in the next few days...household jobs permitting