need help/ electrical question/ short circuit/ brake problem/I REALLY HATE MY CAR!!

[droptopford 5 0]

ok, after successfully driving around with the new t-5 swap in my 94, i notice that my blinker light on the dash doesnt work, nor do the blinkers themselves, and my brake lights as well... i checked, and sure enough fuse 9 was blown ( 15 amp blue fuse connects all of these functions) i then replaced the fuse to find out that my blinkers and hazards now work fine again, until i tap the brakes when it blows another fuse. i then thought that maybe the brake on/off switch had gone bad ( located on the brake pedal rod itself near where it connects to the master cylinder piston) i then proceded to remove the switch and jump the plug with another wire to simulate hitting the brake without actually using the switch. sure enough i blew another fuse telling me that the switch itself is good. after looking at a wiring diagram in chiltons, i can follow the two functions (blinkers and hazards) as well as brake lights switch and wiring all the way back to the rear tail lights and the only disruptions in the connection are the brake on/off switch (tested fine) and something labeled a "multi-function switch." since this switch includes the flashers and brake lights(except for the 3rd brake light) im guessing that this switch is what allows the rear taillights to have two stages and act as running lights and brighter signal lights. my only question about this is where might this be located????. i also know that all of the bulbs are working fine and none of them are blown. this sounds to me like a short circuit, but i have no clue where it could be. thinking earlier that it had something to do with my aode-t5 swap, i double checked everything i did and am 90% sure that it is all fine. (with the exception of all of the wires that connect to the t4mo computer i changed since it is minutely possible thta it occurred there even though it doesnt appear to) any places to check for this switch or any other causes of a short except for: this switch being faulty, a frayed/crossed wire would be VERY MUCH APPRECIATED!!! thanks for your time and effort, Kyle

 

[droptopford 5 0]

bump, i need to get this fixed by tomorrow when i get back from work. ivenarrowed it down to probably being the multi switch in the steering column. however, i just dont know if its more likely a short rather than a bad switch, does anyone have an idea if this is right, or how to test it??

 

[tmoss]

If you need a diagram, you can find one at:

www.veryuseful.com/mustang/tech/engine

 

[droptopford 5 0]

alright, ill be tearing it apart again now, i will check the multi switch first, then the harness leading to it second, any tips guys? i will; check later on tonight

 

[mo_dingo]

alright, ill be tearing it apart again now, i will check the multi switch first, then the harness leading to it second, any tips guys? i will; check later on tonight

The electronic flasher is fed by a red/white wire from that fuse directly. From the flasher, a white/red wire feeds the multifunction switch. From the switch, it goes out to the lights.

But if it takes the brake pedal to pop the fuse, I think you can isolate it to the multi-switch, which feeds the left stop lamps with a light green/orange wire and the right stop lamps with a orange/lt. blue wire.

The BOO switch directly feeds the trunk lid/3rd stop lamp. So I would disconnect the multiswitch, and press the brake pedal, and see if the fuse blows. If it does blow, then it's in the wiring to the trunk lid/3rd stop lamp or the lights themselves.

If it doesn't, then it's the multiswitch, the wiring to the left/right stop lamps or the lamps themselves/connectors/etc.

Eliminate and isolate. You don't need a whole problem, you need half a problem, and another half and another half, etc. If it's the wiring going to any of the lamps, run a new wire instead of digging through wire loom throughout the car. But start with connectors/connections first, as they are the most succeptable to damage.
Scott

 

[droptopford 5 0]

ok, to put it simply, everything is all set.
after checking every single possibility of a short/ bad switch/ bad connector to no avail, i decided it was time to snip the third brake light so i can use my brakes temporarily until i find a permanent fix. i eventually narrowed the problem down to a short or bad connection with the 3rd brake light or the wires leading to it. after about 15+ hours of searching, and 5+ hours of research i decided it was finally time to start chopping away and rewiring. WELL, ,when i was following the wire out from the BOO switch to where it meets the rest of the harness, i noticed that i had pinched a couple wires under my brake/ clutch pedal assembly when i did the t-5 swap. sure enough this was my short connection. so after all of this frustration, im glad all it took was time, about 15 fuses, and lots of swearing. thanks again mo dingo, and i can just hope that that avatar of yours brings everyone else as much luck and help as it has me, lol

 

[mo_dingo]

ok, to put it simply, everything is all set.
after checking every single possibility of a short/ bad switch/ bad connector to no avail, i decided it was time to snip the third brake light so i can use my brakes temporarily until i find a permanent fix. i eventually narrowed the problem down to a short or bad connection with the 3rd brake light or the wires leading to it. after about 15+ hours of searching, and 5+ hours of research i decided it was finally time to start chopping away and rewiring. WELL, ,when i was following the wire out from the BOO switch to where it meets the rest of the harness, i noticed that i had pinched a couple wires under my brake/ clutch pedal assembly when i did the t-5 swap. sure enough this was my short connection. so after all of this frustration, im glad all it took was time, about 15 fuses, and lots of swearing. thanks again mo dingo, and i can just hope that that avatar of yours brings everyone else as much luck and help as it has me, lol

lol. My avatar????? It only brings confusion to those not into the vampire occult.