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Topic: Relay modification for ign sw discussion (Read 10427 times) previous topic - next topic

Relay modification for ign sw discussion

Reply #60 –
humm,, now that you put it that way, let me think out loud here for a moment.

In order to insure we "keep" power train circuits on the igntion switch which is good advice, then moving the GY/Y is not advised.
look at page 24 of my EVTM so i dont have to wait for your new vendor data.

You can also look at page 24 of the evtm on here by going to page 1, post 1.  RIght click on the image and save as a jpeg on your pc.  Open up the file on your machine then you can zoom in and around ect.


The GY/Y wire (group1) is hot in run and it also powers up all the BLK/Lg ACCY (group3) circuits as you would expect.
The Accy circuits are the only real "non-power train" loads

If i follow your advice, then the best thing to do is move only the ACCY circuits to a slave relay.
additionally i should move the heater over to accy as well in my opinion so its not on the GY/Y "run" anymore and anything else "non" power train related.

at the end of the day if i move just the accy ckts to a slave relay, i can keep the GY/Y on the ign switch because of the fact that non essential ckts are slaved to the accy relay.
The blulk if not all "essential power train ckts are on the group1 Gy/y conductor.

this may require me to work on the wirng after the fuse box like as an example the blower motor is is on fuse 9 (30A).  I may have to move this ckt onto the slaved relay with a new fuse 30a fuse.

following your buttstuffogy, moving only the accy ckts to a slaved relay, then moving all non essential ckts to the slaved relay will equally lighten the load on the GY/Y wire and the whole ign switch~therefore= the gy/y group 1 wire can stay on the ign sw.

this is kind a game changer , it really does add a lot more tasks to the job.

the way i was doing it, i was taking the risk that i may be on the hook by moving only two conductors.  since i own the car, i am probably willing to risk that.

thoughts?
because i totally get what your saying..... just thinking out loud here, thats all.

Relay modification for ign sw discussion

Reply #61 –
by the way TOM
i know you said im looking too deep at group3 ACCY and your also saying in so many words, my switch is bad.
It is not a bad switch when all three do the same thing.  When i found this momentary contact, it changed a lot.  You should go get an ign sw and tone it out just as i show on the diagram , you will also find a momentary contact being made on the Blk/lg and the BR/Pk.  No the switchs are not defective, two are spares and one is just hours old, all three act the same.
you will also find that when you slide to accy, you have continuity over to the terminal that is reserved for accy.

I believe that slaving the ckts upstream of the fuse panel requires us to look at this deep , and at the end of the day, i am in no uncertain terms ready to tamper with group 2 ckt 16.. its just too tricky and not enough load to risk the consequences.

Relay modification for ign sw discussion

Reply #62 –
Actually Jay i have many slave relays on the Midnighter. I fond a voltage drop on the injector bank and wired them with a slave. Also i slave the Fuel pumps with a relay in the trunk. As i have found stock wiring is lets say marginal at best in some cirspoogestances. But when you slave out the ignition switch you will find the heat drops like a ROCK. Also remember i totally gut the wiring harnesses on my own cars from soup to nuts. This way i can break down the ircuits with little heat going to the ignition switches. Other than that those 75A relays are Pretty reliable. In fact if you use a double throw relay you can wire it in as redundant. Now i have you totally confused. But you are sharp and i bet you will figure that out in a couple of seconds after reading this. So wire a double throw 80A relay in redundancy and call it a day.
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Relay modification for ign sw discussion

Reply #63 –
a single doube pole relay wont work because ACCY and RUN do not follow eachother half the time, and the other half they do

a double pole would work for RUN but when you go to accy, you do not want run to energize.,, since the DPDT relay has a common coil, you wont be able to control and separate ACCY differntly from RUN.

IM not going any deeper into the ign sw than on the primary side of the fuse box. 
im not going to custom wire things which will cause me to dive into this too deep.  I am not going to revamp my harness for  this mod, its not the point, the pont is to keep it simple, i hoped you had that layout drawing for a single relay.
I tried to do a single spst and a dpdt , neither check out on the truth table.  ACCY acts opposite and the same as RUN...depending on where your key is.

Maybe i need  a DPDT NAND relay,, joking.

Relay modification for ign sw discussion

Reply #64 –
ok,
i tested the temperature on the GY/Y wire and the Bk/Lg, neither exceeded 100deg

I was unable to make more than 22A appear on either conductor in any conditon both while KOER or KOEO,

I dont see a reason to install dual 75A relays,  My TYCO icecube 40A x 2 should be plenty sufficient.

thoughts>?

Relay modification for ign sw discussion

Reply #65 –
RELAY fails no tow truck!!!

I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Relay modification for ign sw discussion

Reply #66 –
The GY/Y on swt position 1 and the BK/LG on swt position 3 have no power while cranking. If anything there was needed for the engine to run it would not start.

By the way, your "toning out" of the switch confirms that the page 24 diagram is correct. The two A1 terminals are the two ends of the ACCY-RUN jumper in swt position 3.

Relay modification for ign sw discussion

Reply #67 –
wrong circuits tom,
 
need to move:
ckt 687 (group1 GY/Y "RUN")

and

Ckt 287 (group3 BK/Lg "ACCY") 

and put them both on one relay

Relay modification for ign sw discussion

Reply #68 –
The make before break between Start and Run makes sense. The R/LG and BR/PK wires are powered by the Start position of swt 3 while cranking and the Run position of swt 2. (The stuff needed for the engine to run)
So to not have a power dropout between Start and Run makes sense.

Relay modification for ign sw discussion

Reply #69 –
exactly, thats what i traced out and concluded.

your gonna have to get your magnifying glass out to see the error(s) i find on the page 240 schematic and compare to page 24 for group 3.
they show an addiitional bonding jumper between ACCY and LOCK on group3 on page 240.
they also show I2 (eye2) bonded to "run" in group3 on page 240, this is very differnt from page 24.

Its my belief that the jumper we see in group 3 is the make before break contactor to keep power on during transition to start.
this also makes me believe that there should be a schematic illustration showing group2 Run is connected to group3 ACCY while in Run.

Enough on this bonding jumper stuff though guys, its moot ,,, ive learned more than enough to understand that i have a lot of respect for the ign sw and they were successful in cramming 20lbs of  in a 5lb sack.

so , dual relays for this and,, lower amperage ok ?

im thinking of dual 40A relays with the single 80cb over current protection.

Relay modification for ign sw discussion

Reply #70 –
Just wrote that up quick as an example. Once again without my prints i am shooting from the hip. Either way a 5 pr0ng relay can be used as redundancy. Just saying. Kick this around for another day or two but the bottom line is slaving out the one circuit that draws the most current is the bottom line. Carry on men!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Relay modification for ign sw discussion

Reply #71 –
will do,, should be able to do this tomorrow, looks all settled then.

Relay modification for ign sw discussion

Reply #72 –
Relay fails no tow truck!!

I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Relay modification for ign sw discussion

Reply #73 –
ok race fans,
here is what i consider the final version of the ignition swtich mod we all contributed to.

pls advise if its ok to bless, and call it good.
I am now building my mounting plate to hold all the goodies to mod headlamps, marker lamps and ignition switch complete with a new fuse bank.

this design offers a little bit more detail, it also explains how if the mod fails, you can always revert back to the original ign sw design so you can stay "off the hook" , thanks tom for getting me to think about that and build it into the design!!!!!!!