Modded Mustang Forums banner

1 - 18 of 18 Posts

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #1
how is it possible that the 12V wire going to my ignitiopn box is run to a chassis ground. i traced it back to the box just to make sure. it's grounded in the engine compartment, right next to the driver side strut tower. how is it possible that it still runs. runs crappy, but it's still running. the ignition box whines too. the whine is directly affected by rpm. which screams bad ground or grounded power wire. but, the power wire being run directly to ground? doen't make any sense.
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #2
no thoughts huh?
 

·
Registered
Joined
·
4,781 Posts
Sure it's not the ground wire? Are there 2 wires going to ground? there should be at least one. Maybe it is wired backwards with the ground to 12V and the + to ground??
 

·
Registered
Joined
·
3,659 Posts
So it is going to ground like directly to the chassis and not to the stud on the solenoid where things are normally attached as a +12v source? Yeah, that is odd. I'd triple verify your tracing and thoughts before you go switching anything.
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #5
yeah, it's going directly to ground. and ryan, i'm sure it isn't the ground. it's the red wire. no splices, no extensions. it's wierd. i've got the whole thing unhooked right now. i'm going to rewire it tomorrow and see what's what.
 

·
Registered
Joined
·
4,875 Posts
Just because the wire is red doesn't automatically make it a power wire. I've heard ignition boxes make noise before. I'm not sure how it would be possible for the 12v wire and the ground to be wired backwards and it still work, but I've seen some weird **** in my day, so however unlikely that is, it could happen... still stressing the highly unlikely part.;)
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #7 (Edited)
Just because the wire is red doesn't automatically make it a power wire. I've heard ignition boxes make noise before. I'm not sure how it would be possible for the 12v wire and the ground to be wired backwards and it still work, but I've seen some weird **** in my day, so however unlikely that is, it could happen... still stressing the highly unlikely part.;)
ok, i'm not an idiot. i don't automatically assume "hot" because i see red. like i previously stated, i traced it back to the ignition box. there are no splices in the wire. i'm absolutely sure that it is the power wire.

and, i'm not sure either how it would work, but for some reason, it's running. :dunno

and, in many cases with DC electronics, if it's wired backwards, it simply workds backwards. 180 degrees out of phase. i don't know if this would apply to an ignition system. but i'm sure it wouldn't help it at all. :D
 

·
Registered
Joined
·
4,875 Posts
Haha, never said you were an idiot. Is the wire actually labled "12v in", or something similar? I only ask because I've seen ground wires all kinds of colors before and its easy to assume the red wire is positive, I know I've done it.

DC electronics rarely operate out of phase when wired backwards, especially when there's circuitry involved, unless it is a reversible DC motor, or a car speaker/subwoofer, but those actually use AC current... Believe me, my job is based on DC electronics, if they worked backwards, I probabaly could have avoided a few burnt pieces of equipment in my day.:D I would be pretty amazed if that unit was wired backwards and still working. I would try to get a wiring diagram for that unit before you re-wire it, just to be safe. I'm sure they have them on their website, or if not, give tech-support a call.
 

·
Who Care's ... Boost It!
Joined
·
538 Posts
Just because the wire is red doesn't automatically make it a power wire. I've heard ignition boxes make noise before. I'm not sure how it would be possible for the 12v wire and the ground to be wired backwards and it still work, but I've seen some weird **** in my day, so however unlikely that is, it could happen... still stressing the highly unlikely part.;)
+1 on the first part. I had electric fans and automatically thought the blue wire was power and black was ground. I connected them and had a pile of smoke. Read the directions and it said black was power, blue was ground. I was like WTF!?!? So saying all of that jibberish, just relax, look at the wiring diagram on msdignitions.com on your make msd box and see what's where and you should be able to track it. I to have seen some half ass f'd up **** myself so be careful.
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #10
Haha, never said you were an idiot. Is the wire actually labled "12v in", or something similar? I only ask because I've seen ground wires all kinds of colors before and its easy to assume the red wire is positive, I know I've done it.

DC electronics rarely operate out of phase when wired backwards, especially when there's circuitry involved, unless it is a reversible DC motor, or a car speaker/subwoofer, I would try to get a wiring diagram for that unit before you re-wire it, just to be safe.
true true. i wasn't thinking very broad when i made that statement.

it's got a digram on the back of the ingnition box. i took it all off, and rewired it all over. when i got more into it, i saw that whoever wired this thing in the first place created a 12v junction which screwed right into the chassis. great idea, huh? :lmao it had a few other wires going to it and i traced them to the 12v constant on the radio and one was just hanging loose behind the dash. it was running off of a lead from the ignition switch. i almost crapped myself when i figured out what was going on. it makes no sense whatsoever to do that. it was however insulated with rubber washers and some electrical tape wrapped around the screw to keep it from grounding. needless to say, i did not hook it back up that way. sadly, my battery is completely dead and won't take a charge or a jump. so, i couldn't see if the whining noise was gone. it's got a short to ground somewhere that is killing the battery. i'm really looking forward to tracking that down. any suggestions? i read somewhere that the voltage regulator could go bad and leak voltage to ground. i also found a new voltage regulator in the hatch, which leads me to believe it needed to be replaced and just never happened.

side note: there's a moroso sealed battery box in the hatch. if anyone wants it, you can have it.:D
 

·
Registered
Joined
·
4,875 Posts
I'd be interested in that battery box.

As far as the short problem, I think ryans88gt had a problem with his regulator drawing current.. or at least thats what he was leaning towards last I heard. The way I check for draw is to start out by narrowing it down to an individual circuit. Either use a multimeter with an ammeter or a cheap one clip, one bulb, test lightand break open the positive side with the tool of choice (If you don't know how to do this I can explain, but for right now I'm going to assume you do). Just start pulling and replacing fuses one by one until you see the draw go away when you pull a specific fuse. Then you know what circuit the draw is coming from. Even a normal car with a computer will draw a small amt of current with everything off so the draw will never go completely away, but it will go down to an acceptable level once you find the right circuit (usually less than 0.2a.. and thats for cars with BCM's too)... also when checking for draw, don't forget to pull your domelight if you have the door open.
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #12
i've gotta get some juice in the battery before i can do any of that. but the freakin thing won't take a charge or a jump.
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #14
yeah. i was gonna go get another tomorrow.
also, where's the voltage regulator? noob stuff, i know. i figure i'll go ahead and throw the new one on there while i'm at it.

further information about short in system: i was moving the ignition box around the other day (it's inside the car, on the trans hump) and i hit it against the metal frame of the dash where the radio mounts. (the engine was running at the time) and, it threw a little arc. assuming that the chassis of the ignition box is grounded, this implies that there is enough voltage running through the body to make some fireworks.

i see a long expensive road ahead for my poor car. :(
 

·
Registered
Joined
·
4,875 Posts
Generally, the casing should be grounded on electronics like that. The body of your car is ground also. If you saw an arc between the casing and the body of the car while it was running, that tells me that the ignition box has a poor ground. I'm assuming you took care of this when you re-wired right? Make sure its cleaned piece of metal (no rust or paint) and of proper gauge wire. Maybe its an internal problem with the unit and it has a weak ground connection on the actual ground wire (corroded, partially blown trace, ect.) and was getting a good ground through the casing (would explain the arcing), if thats the case, ground the casing to the chassis of the car too... poor ground on the box may explain the car running rough.. maybe not, but at least you can rule it out after that.

As far as the regulator, I'm not too sure, I haven't had my car together in a long time, much less know even where my alternator is, come to think of it... I think they are internal on these cars, meaning inside the alternator, but am not 100% on that one... hell I'm not even 50% on that.
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #16
yeah, i made sure it was run to a good ground when i rewired it.

should i run a 4awg jumper from the neg. terminal to the body? right now, it's got one of those thin little ribbon looking bare wires bolted to the body. i doubt that has anything to do with my issue, but it just looks like a shitty connection to me.
 

·
2008 Hammock Rodeo Champ
Joined
·
1,227 Posts
Discussion Starter #17
yeah, i made sure it was run to a good ground when i rewired it.

should i run a 4awg jumper from the neg. terminal to the body? right now, it's got one of those thin little ribbon looking bare wires bolted to the body. i doubt that has anything to do with my issue, but it just looks like a shitty connection to me.
GROUNDING STRAP!! that's the word i was looking for.:D

<---might be retarded.
 

·
Registered
Joined
·
4,875 Posts
/\ /\ Always a good idea to do. While you're at it, run a 4ga ground from the point on your chassis where you grounded the first one, right to the engine block too. You can never have "too much" ground, but you certainly can have not enough.
 
1 - 18 of 18 Posts
Top