Fox T-Bird/Cougar Forums

well, this afternoon has been fun,

88 bird 5.0 no start
no starter relay click
no eec relay click
no fuel pump relay click
no power windows
no turn signals
no hazards
headlamps work
marker lights work
instrument cluster intermittant
all fuses good
all solenoid fuse links have continuity and power downstream

pulled the car 20 miles with a chain and got it in the garage
pulled off the starter relay red/blue wire and with koeo there is no power.
,,should be low voltage around 5v with key in run and full battery in start..i have nothing in both key positions.


continuity and voltage check all fuse links down stream of the starter relay and all have power out.
litterally ripped all the wire loom off the drivers side up to entry at the fire wall to inspect the red /blue and parallel white/red wire for damage and there is none.



....moving on to the ignition switch and it fell apart off the column, its a  to remove anyway but put on my good spare right away.
my son was back probing the ign sw terminals and said he had no power anywhere,, humm,,, impossible i say.
Rechecked the fuse links but did not do the ing sw back probe myself, will do tomorrow.

Problems in the bird are from what i see have only one common point which is the ign sw but the replacement i put on yields the same results which really sucks.




so it appears i found the problem, no power delivery to the starter relay but even after i swapped out another ign sw, also swapped in another starter relay and also verified fuse links are good, this is starting to sound like a dash board nightmare,, any thoughts?

I am going to inspect the Fuse 1 termination on the top side of the fuse panel to see if it somehow came undone, evtm shows the power for the starter relay passes over one side of fuse 1, not across it therefore justifying the upstream requried fuse link.

whats really making me sick is that mason said he smelled melting plastic while i was pulling him, he had his marker lights on which do work along with headlamps but the markers where the only thing on besides his key switch in the run pos.


I suppose my next logical step is to move on to the Neutral safety switch, that would open this circuit i am troubleshooting.


three questions:
***ANYONE GOT AN 88 evtm page for the start circuit, my 87 evtm does not include the starter relay white/red wire.

***can anyone tell me how thier bird solenoid wires hook up, mason has battery with all secondary ring terminals on one post and the starter cable on its own on the other post.  this doesnt seem right to me, my coug is not like this but its an 87.

*** i belivet he previous owner converted to a floor shifter from column, would the N safety switch still be on the transmission or is it a micro switch on the shifter?  my gut says its still on the transmission.

I had a problem last year where I had no radio and no cluster. tracked it to the ignition switch, the switch was fine, but the grey/yellow wire had melted the connector shell and pulled back enough to not be making contact with the switch terminal.  I replaced the switch AND reshelled the connector.  Not saying it's related, just reminded me of it by your description.

I was thinking ignition switch or connector also.  unless you have melted wires somewhere it really cant be much else.

I thought I had read somewhere, whether it was on this site or another one, I don't remember... but anyway, our cars have known issues with wiring failures, most having something to do with the ignition switch.  I know on both of my birds, the TC and my old LX (May she rest in piece), the ignition switch was defective and had melted both the wiring and the connector.  At any rate, I recall reading somewhere that the ignition and headlight switch pigtails were available.  Maybe someone who has replaced them can provide part numbers, etc.

Power to the starter relay appears to actually originate through the ignition switch -> neutral safety and comes in on the W/PK.  The R/LB routes this power to the TFI.  You said that you checked the downstream side of all fusible links, but with Links E and C inline, it might be very easy to hit one and miss the other.  If good, I would look closer at the ignition switch and verify power into the switch on the Y  wire(s) and verify power out in run, at the switch on both R/LG and BR/PK.  If good look at fusible link D.

I suspect that you may have had a wiring meltdown which may have shorted circuits, damaged connectors or opened up one or more links.  Unplug connectors and trace.

Good Luck!

that 88 evtm page is a totally different layout than the 87evtm with respect to the color coding of the red/light blue.

notice how the red light blue transitions back in the game though up on the ign sw , sources as white pink but changes color.

odd.
I almost have to question the red light blue off the starter relay because my red/blue and white/pk wires go direction into the passanger compartment.
If the red / lb wire were to go to the TFI, then its looping back out through another path.


any input to the connections made on the starter relay i mentioned earlier.

anyway, going out to install a "new" ign sw and retest for power at the ign sw itself.

nope,not a single ounce of power to the ign switch.. tearing up the fuse panel now to get to the yellow wire that bonds to fuse 1,, i wish these seats poped out like the wifes karmanGhia.. flip a lever, slide em forward and they are off the track.

hey, i just found the black fuse link(s)
This is a major difference from the 87 to 88 evtm.

the black fuse links are located and spare wire looped back into the harness that is underneath the battery tray.
found one of the black fuse links blown, this allows power upstream to the ign switch.

too bad i have a lot of buttoning up to do on the inside.
should be good to go,,, will see

thanks for that evtm page, ~!

To test and verify (not leave it this way), you can jumper around the fuse link... BUT those don't fail without a reason, so you likely have a direct short upstream in your harness, unless of course it was caused by a faulty ignition switch, in which case we can thank God that the fuse link worked and prevented your 'bird from a fiery death.

OK you have a power distribution issue. The main buss that comes off the solenoid is open. You may have a bad ignition switch but you posted no HAZARDS which are void of the ignition switch. You have an open fuse link. Or a bad connection at the solenoid. To check this get a length of wire and back fees positive battery to the heavy alt lead. If the car gets power back it has an open fuse link or main power lead feeding the cab. Good luck.

the 88evtm page posted shows 16awg fuse link, in reality there are three that bond a couple 8awg and to save a long story, the existing green fuse link is in place and good so............

so, to repair i feel comfortable installing dual #12 awg's in place of the tripple 16ga.

16ga is 2580 circular millimeters of copper x 3= 7740 total copper which is equal to a little better than a #12ga single fuse link.

now #12 is good for 30amps at 90deg C in cable tray or in our case in a bundled tight conduit so to speak.
#12 is good for 40A free air at 90degC.

so,, i think i may fuse this up but a little stronger ,,,, i say this because there are likely many more points of high resistance in the car entierly.  Mason typically has about 11.2 v on various circuits with the key off,, i may cure some of that with this... will put a heavy burden on the single green fuse link that feeds all this garbage but hey,, atleast there is still protection.

stay tuned,,

thanks

I am confused!!! Did you already know where the fuse link failed!! If so why did you post it!! Seems like you just wanted to UP grade the links. So why ask the questions you did. Am i missing something here???

Get an inline mega fuse holder.  Easier to replace than a fuse link, just sayin.

I had a problem yesterday evening, i troubleshot today and yesterday with some spare time.
Thanks to the 88evtm page, i dug into the harness under the battery tray and found the black fuse links. 


You may not have had time to read my previous posts,

Car is up as of a couple minutes ago.  If i went by the 87 evtm ,i would still be shot gunning it tracing out no power up at the ign switch. 

Car runs,, now gotta button things up with mason tomorrow.

Well had to be a link it is the only thing that controls all the power feed to the cab and car. And they are around the battery area. Maybe this will help. A fuse link is selected to protect a wire by using one 2 sizes smaller than the wire it protects!!!  So a number 10 wire should have a number 14 protecting it. Hope this helps.

all is well now, i do appreciate the 88evtm page,, again it is very very different from the same car in the 87 year.

the fuse link that was my problem was the black ones but they were deep within the plastic tubing that is under the battery tray,,within that mess resides the three parallel black 16ga links.

without the evtm, i would be guessing.

i saw that group of fuse links entering the plastic tube and thought for darn sure those must be for headlamps / related to headlamps ect but im glad i asked the question here, cleared things up real quick like.

thanks everyone

The three black 16 gage links b, c, and x feed seperate circuits and are not in parallel. Don't see how you can safely replace them with two heavier gage links.
Link C that feeds the ignition switch also feeds a couple of fuses. Link B feeds another group of fuses. Link X goes to the alternator regulator.
My scanner out of service, maybe TheFoeYouKnow can post page 26 Charge/Power Distribution from the EVTM for you.

I am curious, Jcassity, do you have a 3g alternator wired in this car?

For what it is worth how about this??? Those fuse links around the battery are a pain and i sometimes do this.


(http://i740.photobucket.com/albums/xx46/proguns/001-122.jpg)

I was speaking in general and using the term "parallel" for a visual discription only, yes they are separate circuits.
For your viewing pleasure and disgust, keep in mind these three 16ga black fuse links all bond to a common single yellow which then further upstream bonds to a green 14ga fuse link that is connected to the coil.
With low battery voltage conditions and max ampacity demand from the alternator, thats a huge demand on a 14ga to feed all those down stream circuits.
My clamp on showed approx 56A of continuious demand on the alternator lead with a low battery.  The battery itself was commanding approx 23A but that will go away as charge is applied.

yep, sure do

http://www.stangnet.com/mustang-forums/threads/advice-on-fusible-link-to-maxi-fuse-what-amperages.819889/

Good info on what amperage to select when swapping links for fuses.  remember that the table refers to the size of the circuit, not the size of the link.

well, just for the record, i deleted all three of them for a good reason.
They are all three tied to the one common green fuse link which i kept.
this will help eliminate probable faults later.
As softtouch said, all three black links protect three or so separate down stream circuits, one of which delivers power to the ign sw. At the end of the day, all three 16ga black links are protected by the one single green to yellow fuse link terminal at the starter relay.  This may only be true for the 88year,, would be interesting to see if this is true or not, will compare to my 87 2Oth.  Anyone with an 87sport chime in.

a few pics of the area
down low near the battery holder is a round spot in my harness of trouble that represents the several wires i bonded to a 4awg burndy barrel lug.  Prior to crimping, i slipped over a farily large diameter 1 or so inch long rubber boot that i trimmed off from a spark plug boot.  i crimped it then slipped the boot over then taped.

The only benefit i see in having these three separate 16awgfuse links is for circuit isolation, in my opinion, the upstream fuse link still carried the burrden of all three downstream small awg links so its moot to me.  When the green one fails, at least the car will not have accy ckts working but no start making it really clear to me there is a fuse link issue and now, only one to repair.

I looked at he green fuse link and its called out to be 14awg, after disecting a spare and using my cir/mil copper measuring device, it appears this is not actually 14awg but somewhere along 15 and further i would estimate its closer to 16 than 14.  oddly enough, i compared the spare OEM fuse link to a ANSI/IEEE equivilant 14awg "FLEX" not "STR" wire and the 14awg UL listed non halogen wire i have is just at 14awg and also feels stiffer and also looks bigger.

Its my belief that ford used "str" wire and not "flex" (flex of which has a higher currrent carrying capacity.

either way, try not to flame throw, i entertained the idea of a mega fuse and to be honest, i worry that the fuse by defaut like most fuses is rated to carry 1.5x its nameplate rating which means you may actually need to experience 75A of inrush or over current in order to trip the fuse.  This being said, that would be soely depending on a  highly calibrated fuse element as well.  Power in general happens be be my job so take it for what its worth.  Circuit breakers however typically are rated to 1.25 thier name plate rating and in some cases some breakers have shunt trip which gives them a dead on Trip rating and worth thier weight.

I am seriously considering setting mason up with a few slave relays but since its already been done, i dont want to re-envent the wheel and would rather work with someones tested and tried method.  Might as well not wing it eh.

so back on point, i have one single green 14awg oem fuse link now in command of this circuit but am seriously considering adding a calibrated Heinemann 50A DC circuit breaker in its place which will also come equipped with aux contacts to light up an "in the dash" LED showing the breaker has tripped. 

either way, we all know the oem wiring could be sized at the lease one size larger in most all areas...that we could all agree on.

now let the bashing begin for my cutting out the fuse links.

I still like intelligently selected fuses, but you're the one who has to live with the car and work on it, so when it comes to YOUR car, I'm prepared to go with YOUR preference.  It's nice clean looking work in any case.  Good job.

fuse would be simpler for sure.