Ignition switch wires

[fergarelli]

Okay, so I read all the posts about ignition wiring and am still struggling with reinstalling mine. It has 8 posts, and 6 wires (some of which have two wires on one connector). Anyway, I thought I labeled them carefully when I took it out (5 of them anyway) but for some reason the fuel pump turns on the moment I got to hook up the battery, as if it is in "Accessories" mode. Does is matter that it's not reinstalled the steering column yet? I pushed the steering wheel lock in but still seems to start the fuel pump the moment I touch the battery. Btw, the posts on testing the switch and the connector box off of the starter were a HUGE help. Any tips are much appreciated. Sincerely, Eric

[westy64]

what year is your car ?
having the switch in place should not make a difference.
I have the same trouble but I have rewired the fuel pump and may have missed something.
I guess the pump should start with key on starter position and not on "on".

[fergarelli]

Thanks so much for the reply.
1976 124 1800.
Should the battery be sparking when I connect the negative terminal? That makes me think the switch is bypassed and the car is actually being "hotwired." The switch isn't bypassed altogether (i.e. the car doesn't "crank" when I connect the battery, it just starts the fuel pump when the switch is in the "on" position.

P.S. How do we post images on this website? I hit the Img button but can't figure out what to do next.

[westy64]

Thanks so much for the reply.
1976 124 1800.
Should the battery be sparking when I connect the negative terminal? That makes me think the switch is bypassed and the car is actually being "hotwired." The switch isn't bypassed altogether (i.e. the car doesn't "crank" when I connect the battery, it just starts the fuel pump when the switch is in the "on" position.

P.S. How do we post images on this website? I hit the Img button but can't figure out what to do next.

Mine is a 76 too.
you will find all the wiring diagrams there :
http://www.globallistics.com/spidersweb ... ndex0.html

about the battery sparkling, I would say yes, as the clock is permanently on.
maybe you have a door open, and then the courtesy light is also on.
if both your clock and your courtesy light do not work BUT your battery sparks, then you do the test of the battery linkage while you remove the fuses one after the other, until you find which one cancels the spark.

then you print the diagrams, and you work on the identified fuse diagram.
can be a headache.
you can also be lucky and find quickly the wrong connection.

good luck !

[gionetz]

Does this look like your setup? (this is my 75 ignition switch) Maybe there is something I can do to help if it is i.e. check certain wires but!, I am having an issue myself, I did note that one of the terminals not used on my ignition switch is "always live"...maybe you hooked the pump up to that one?, and the one my green/black and gray one are connected to do not liven up when on run, thus the PO rewired the fuel pump leaving me to wonder which feed usually makes the pump hot, brown or black? Let me know if you want me to check anything out for you, no guarantee that it's right though! good-luck

[westy64]

Does this look like your setup? (this is my 75 ignition switch) Maybe there is something I can do to help if it is i.e. check certain wires but!, I am having an issue myself, I did note that one of the terminals not used on my ignition switch is "always live"...maybe you hooked the pump up to that one?, and the one my green/black and gray one are connected to do not liven up when on run, thus the PO rewired the fuel pump leaving me to wonder which feed usually makes the pump hot, brown or black? Let me know if you want me to check anything out for you, no guarantee that it's right though! good-luck

my 76 is wired the same.
this green/black and gray used to be an enigma, as it is not supposed to be this way according to the diagram
http://www.globallistics.com/spidersweb ... emes/7.jpg

but I know now that the cars are not wired tis way. Green/black and Grey wires are linked at the ignition switch and not at connector C23 as stated on the diagram. Doesn't change anything anyway.

About those green/black and gray wires, here is my understanding.
They both leads the power to the fuel pump, but not at the same time.

1) engine not running.
Oil pressure switch is closed and "sends" a ground signal to the oil pressure indicator at the dashboard (when key is on), and also sends this ground signal to the fuel pump relay (wire grey/yellow). In this case the relay is closed for the 87b terminal that sends a power signal to the pump, through the grey wire. Relay is powered by the pink wire.

2) engine running.
Oil pressure switch cuts the ground signal, then the relay does not operate the grey wire anylonger.
And I guess that the ignition switch delivers power to the pump through the green/black wire.

I still need to investigate on the ignition switch side, to understand which terminal those wires are connected to.

to be followed.

[gionetz]

VERY helpful! Today I will try and energize the green/blk and grey when running to see if the relay is working, because my switch is faulty, I cannot test whether they usually get their feed from black vs. brown. Thanks, this is great!

[westy64]

VERY helpful! Today I will try and energize the green/blk and grey when running to see if the relay is working, because my switch is faulty, I cannot test whether they usually get their feed from black vs. brown. Thanks, this is great!

Be careful while testing the relay.
1) is your fuel pump relay the original or a replacement one ?
2) if replaced, was it replaced by a similar, or by another model , and the wiring modified ?
3) I am still missing something with my understanding of the fuel pump powering.

I assumed that theses two wires (green/black and gray) do both power the pump, in two different moment : engine running or not.
In this case, one of them is powered only when engine is off, and so it should be powered at the same time as the starter.
Is there a second blade under the ignition switch that is powered with the red wire (starter ?)

I am far from my car at the moment, and my engine doesn't start so far so I cannot do the following tests :

a) check if the oil pressure switch gives a ground when engine stopped.
b) check if it cuts the ground when engine is running.
c) is there 12v power on connector 87a on the relay with ignition on, engine stopped
do we have these 12Vat the fuel pump, even when green/black and gray wires are unplugged at the ignition switch ?
d) is there 12v power on that connector when engine is running ?

I hope I am not completely wrong about it...

[gionetz]

I'm glad we are on the same page, I just thought of this myself this morning..I was thinking that "perhaps" the current tab it's connected to only gets powered at start, like the red...thus sending a signal to the relay to kickstart the fuel pump until the engine is running allowing for all the oil-pressure junk to happen. The PO cut the green/black and tapped it into a blue/red that's hot during run but left the grey connected to the tab, I tested the tab during "run" but NOT in "start", I will get out there in a bit and see if the tab with green/blck and grey gets energized during "start" only, this is def helping, I've learned more here about this 75' switch here than anywhere else so far, nothing seems to match up!!! ....we got this lol!!!!

[westy64]

I'm glad we are on the same page, I just thought of this myself this morning..I was thinking that "perhaps" the current tab it's connected to only gets powered at start, like the red...thus sending a signal to the relay to kickstart the fuel pump until the engine is running allowing for all the oil-pressure junk to happen. The PO cut the green/black and tapped it into a blue/red that's hot during run but left the grey connected to the tab, I tested the tab during "run" but NOT in "start", I will get out there in a bit and see if the tab with green/blck and grey gets energized during "start" only, this is def helping, I've learned more here about this 75' switch here than anywhere else so far, nothing seems to match up!!! ....we got this lol!!!!

the more I look at all the parts (ignition switch pictures) and diagrams, the less I believe my own theory.
the diagram shows the green/black connected to blade 16, but this output of the ignition switch is never described.
I will check with the ohmmeter if 16 and 50 (red wire) are connected when key on start.
Blue/red is just like pink or blue/black, power when key on "run", but it goes through fuse #2.

[gionetz]

PLEASE NOTE: The screw mounting the lock has been taken out before, so...I can't "verify" this is the correct ignition, although it looks like it is..if more photos would help in any way, just let me know, I would love to know what this terminal is "supposed" to to

[fergarelli]

All,
Thanks so much for the help, I think I got it reconnected properly, finally. In the end, I think I do in fact need a new ignition switch. Can there be another explanation for having the wires connected properly and turning the switch and nothing happening, then when I keep turning switch several times the accessories come on and the fuel pump starts? I think the switch is original as the keys I got from PO were so worn I am shocked they worked still. Who knows anymore, at this point its worth getting a new ignition switch to just rule it out.

[SLOSpider]

I have a couple of good used ones listed in the for sale section. I sold the later model one with the wires attached but I think I still have tow of the early ones. Brian

[fergarelli]

Thanks SLOSpider, I was just going to inquire with you about the switches I saw you had in the Parts Section, so thanks for getting in touch. My only question is whether it would work for my car. Mine is a 76 124, 1800 and I saw online when looking around for a switch (International Auto Parts, I think) that one of them said, "for use on cars that originally had a mechanical fuel pump." I'm not sure what that means but I'm guessing that means it has less posts, etc. Anyway, my original switch has 8 posts and 6 wires that attach to it. And I have an electric fuel pump. Do you think your switch will work? And I'm not sure if you still have that radio but I'd be interested in that as well. I have some Def Leppard tapes I've been dying to get out and cruise with.

[westy64]

Def Leppard not compatible with Fiat.
Only Nino Rota.