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Topic: Relay modification for ign sw discussion (Read 12774 times) previous topic - next topic

Relay modification for ign sw discussion

Reply #15 –
Quote from: hwy73;405054
Makes sense to me.  The "Hot-in-Run" powers almost everything in the car and is "on" whenever the car is being driven, far longer than the other two circuits ("accy" and "hot-in-start").
All three circuits are "on" when the car is being driven.
 
Quote from: jcassity;405058
will do volt and amp readngs today on all conductors "large only" to see and provide further information wtih all items powered on that i can.
another interesting fact is this,
on my son's bird, the two yellow inputs were over heated and the insulation had changed from yellow to dirty tanish color at 2 or so inches where they bond to the ignition switch.

the yellow(s) appear to be thhn wire around 8awg just by feel and if engineered to the free air rating, the wire size is ok but its not free air, the wire travels through wire mold and duct so to speak.  Its saving grace is that its probably 90degC rated or better insulation.

i am wondering if i shouldnt pull in another separate yellow from source to the ign sw?

thoughts?
The wires being discolored at the switch says to me that it is a connector or switch contact problem. Not a wire size problem.

Relay modification for ign sw discussion

Reply #16 –
are you thinking three separate relays? 

warming the shop up so i can cypher the internals of the ign sw, there is one section of the internals that has a smaller "shoe" that moves separate from the larger chunk of brass.

also, i figured out why my sons ign sw went bad, the little ball bearing that rolls along the plastic part of the ign switch,, well it wears a groove out and introduces loose connections between the shoes and the contacts, the ball bearing has a rear tension spring that is suppose to keep it under steady presure but it could shrink or loose its tensil strenght.
\
hope you reply back softtouch, your kinda confussing me into my initial gut feeling they are separate "on" circuits,, your prob right though as always.

Relay modification for ign sw discussion

Reply #17 –
Looking at all the wires left to right.

Run----GY/Y on,  R/LB off,  R/LG on,  BR/PK on,  BK/LG on
Start---GY/Y off,  R/LB on,  R/LG on,  BR/PK on,  BK/LG off
Accy---GY/Y off,  R/LB off,  R/LG off,  BR/PK off  BK/LG on
Hope this doesn't make it more confusing.
I'll have to think about the relay configuration a little bit.

Relay modification for ign sw discussion

Reply #18 –
i did that to like a truth table,, the br/pk wire is throwing me off

be back in a while with amp loads on each

Relay modification for ign sw discussion

Reply #19 –
Makes sense to me. The "Hot-in-Run" powers almost everything in the car and is "on" whenever the car is being driven, far longer than the other two circuits ("accy" and "hot-in-start").
 
softtouch : All three circuits are "on" when the car is being driven.
 
Not looking for a g contest......
 
I'm probably not saying it right. There must be some kind of isolation between these circuits. Let's face it, turn the key to "accy" and the fuel pump doesn't run, no HVAC fan, no ECM, (at least on an 88), these are probably the largest of current draws.
Likewise "hot-in-run-and-start" ,only one fuse (18 I think) is listed this way, so they may be all "on" when the car is running, they probably have differnt draws on each circuit.

Relay modification for ign sw discussion

Reply #20 –
Don"t cut the BLUE wire !!!  ;)

Relay modification for ign sw discussion

Reply #21 –
Guess I chased them to pm's with my rhetoric.  :(

Relay modification for ign sw discussion

Reply #22 –
Four relays should do it if you want to cover the whole switch.
Don't grade me on my art work.
 

Relay modification for ign sw discussion

Reply #23 –
Quote from: hwy73;405092
I'm probably not saying it right. There must be some kind of isolation between these circuits. Let's face it, turn the key to "accy" and the fuel pump doesn't run, no HVAC fan, no ECM, (at least on an 88), these are probably the largest of current draws.
Likewise "hot-in-run-and-start" ,only one fuse (18 I think) is listed this way, so they may be all "on" when the car is running, they probably have differnt draws on each circuit.
They are isolated by the different sections of the ignition switch.

Relay modification for ign sw discussion

Reply #24 –
load readings,, did not take any of the "start readings though, didnt see any reason to.
Run conditions: KOER, HVAC HI, radio on, high beams on, turn signals on, driver door open
ACCY conditions: lights off, radio on, driver door open

yellow clamp on amp reading conditions: power windows in motion,  KOER, HVAC HI, radio on, high beams on, turn signals on, driver door open


color........................."ACCY" DCA / V .................."Run" DCA / V
Yellow input............., 1.3A / 12v....................., 35A (normal 20A without window motion) / 12v > large wires
G/Y........................,  .7A / 0v........................, 17.7A / 12v > large wire
Blk/Lb.....................,  .7A / 0v........................, .7A / 12v > small wire
Blk/Lg.....................,  2.6A / 12v......................, 1.4A / 12v > large wire
Br/Pk......................,  .7A / 0v .......................,, .7A / 12v > large wire
Red / Lg..................,  .7A / 0v .......................,,  3.4A / 12v > large wire
Red / Lb.................,,  .7A / 0v.........................,, .7A / 12v 
Brn / wht................,,  .7A / 0v.........................,, .7A / 12v

Relay modification for ign sw discussion

Reply #25 –
going to take a look inside the ign sw now.

Relay modification for ign sw discussion

Reply #26 –
Jay i do these all the time and what you have to do is get the highest load section out of the ignition switch. I do not have all data right now as it is down. I am in transition with a new vendor. But leave the ignition system on the Ignition switch as if the relay goes south a tow truck wont ruin your day. Basically the highest loads are accessory loads that would be the blower circuits ETC. I pick the circuits that are in excess of 30-50 AMPS Cranking circuit can remain on the switch as well as light load circuits. The ignition switch can only handle app 25 A at best. I pick the circuits with an ammeter and use those 75A relays i sent you. Dont over design the system as most do. A single relay is the ticket. So isolate the systems and you will find the discolored wires are the ones that have to be slaved. Remember do not slave the ignition system as a failed relay will leave you stranded.

Looking at soft touch setup looks like a night mare and makes no sense to me. He has cross overs on start and run circuits as i read it. Also to many relays and to complicated and i cant make heads or tails out of it.
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 #27 –
Quote from: TOM Renzo;405105
Looking at soft touch setup looks like a night mare and makes no sense to me. He has cross overs on start and run circuits as i read it. Also to many relays and to complicated and i cant make heads or tails out of it.
No different than making sense out of the stock ignition switch circuit. Just showed how to take all the loads off the switch. He can pick which one or ones he wants to do.

Relay modification for ign sw discussion

Reply #28 –
here are a few ransom pictures of the ignition switch along with the internals.
you can map out the wire colors and where they go on your own using the evtm but just viewing the connector end, you can see where they go.

notice the incorrect statement i made but still stands true.  the ball bearing wears too much of a groove in the aluminum housing and the contact shoes can eventually stop making good hard contact.  Partial contact will increase resistance and then you have two of the three things to make watts,, or heat.~voltage and resistance.

BACK TO THE THREAD,,

here is what i found softtouch,
ignoring the start circuit completely as i dont really want to move that stuff as we had already discussed,

______________________
with key in RUN>>
power comes in on yellow
power is delivered to Run and to ACCY
*Run contactor backfeeds the ACCY contactor while in this position.

With key in ACCY>>
power comes in on yellow
power is delivered to ACCY only

Based on this information and metering out the internals,, do you all agree?
I have revised the Ignition switch drawing to reflect this.
THEFOEYOUKNOW, pls check and revise your 88, Trinom your 86 as well.

Here is what the schematic should actually be like. 
the original shows the ACCY is backfeeding run, not the case at all so there is no doubt i my mind that the below is most accurate.  not the first error we will find in the evtm(s)

Relay modification for ign sw discussion

Reply #29 –
ok, here are a few shots of the ignition swtich itself for anyone curious of whats going on in there.