car keeps running, stupid electrical problem

[e_racer1999]

welllll...... got the battery relocated to the back with a rear mounted cutoff switch on the back panel.

at the same time i was doing that, i did the internally regulated 280ZX alternator swap (and did the diode thing)

anyway, when i switch the battery switch, the car acts as though the key is in the "ON" position - brake light is on and the distributor (E12-80) "clicks" when rotated.

i pulled out a bunch of crappy PO-installed wires at the same time, as well, but those were for the cruise control, etc.

anyone have maybe a check off list? i'm terrible with electrical stuff, so any help would be great! better yet, if anyone in san diego wants to take a look.....

Jason

[geezer]

First thing you should check is the diode you installed. Sounds like you may have it backwards. The band stripe on the end of the diode should be the end going to the alternator. The diode only allows current to flow in one direction. I run S1 alts on my Mopars and have made this mistake before, with the same problem exhibited.

[EScanlon]

Cruise control? On a 72? This must definitely be a PO mounted option.

Otherwise Ron is dead on. Just moving a battery wouldn't cause the problems you're mentioning.

However, are you trying to shut off the engine by killing the battery? Don't know that I would recommend that as a "kill" switch. Use the standard ignition switch, THEN disconnect the battery.

2¢

E

[geezer]

I woke up out of a sound sleep thinking about this. Your diode may be OK. Check anyhow. I'll check tomorrow but if I remember right I had to run my alternator charge wire all the way to the back to the cutoff switch. The reason being, all residual current and all circuits are then shut down. I don't have a schematic that fits your case, but you will be able to figure out which is your alternator output wire. About a 4AWG in size. Good Luck

[geezer]

I checked how mine is wired. It is not nessesary to wire it this way to shut the engine down with the ignition switch (as long as your diode is on correctly). It is nessesary to shut down all circuits with the cutoff switch though and depending what class your running in, it is a requirement.

[e_racer1999]

i triple checked the diode. i recycled the connector off of an old VR and made a jumper. i desoldered the diode and checked it both ways. i still have the symptoms even when the jumper is completely off!

i am not using the cutoff switch to turn the car off, i'm using the ignition key. but in order to get the car to turn off i HAVE to turn off the battery switch.

and yes, the CC was a PO installed thing; moderately well done, but with hideous wires running all over the place.

Ron - i have 2GA wire running to the front of the car into a terminal block that takes another 2GA onto the starter solenoid and a 4GA onto the alternator, so basically mine is wired the same way as yours.

EDIT - actually, upon further inspection, my alternator is on the OTHER side of the switch when compared to your diagram.... but i don't think that would cause this problem, correct?

so basically, my problem is that the ignition key STARTS the car, but doesn't affect shutting it off.... AT ALL. i'm assuming that there's something wrong with the wiring at the ignition switch, and even though i have a schematic, i wouldn't even know where to begin....

[superfunk]

It sounds like you have jumped one section of your ignition switch. You still use to ignition to start the car because that part of the switch is working fine. Try starting the car with the headlights on, do they go out like they should? I'm willing to bet they dont. You have to have the cutoff switch off to shut off the car because it is the only switch in the main line now. I'd say go back and recheck your wiring. I wish I could help you more, but I dont have a schematic in front of me right now.

[geezer]

Jason, I want to make sure we are talking about the same thing here. Is this a Safety Cutoff Switch mounted on the rear/outside of the vehicle to comply with sanctioned rules or mearly a switch to kill all power from the battery when the car is not in use? If used for racing, the alternator output wire must be on the battery side of the cutoff switch, as I show in that miserable example of a diagram. Here's why. This is a safety feature that insures all circuits are shut down in case of a mishap. Clearly marked with ON/OFF and easily accessable by a second party, regardless of the drivers ability to turn off the ignition. Even though the Alternator charge wire remains connected to the battery in this configuration, it is dead ended at the alternator because the field sense has been eliminated, thus no output. If it is just a switch used for simply disconnecting the battery, then that's going to involve some looking into. I'll try to help if thats the case.

[e_racer1999]

superfunk - i'll check it out; the PO did some very strange wiring to the car, so i'm sure the problem lies there. the biggest thing that's buggin me, though, is that it worked fine before.....

ron - currently it's set up to prevent the battery from draining while sitting, but in the near future i'm going to be running the alternator wire back to the battery end of the cutoff switch to be used for sanctioned racing. it is currently mounted on the outside rear, but is not yet marked and apparently improperly wired. but i know how to fix that, just not the stupid car running thing...

[geezer]

OK, Now that were on the same page, you should follow up on Superfunk's suggestion first. Sounds logical to me.

[e_racer1999]

ya, hopefully i can get the head reassembled today and check that out as well...

it still bugs the crap outta me as to why the car was working fine before....

[e_racer1999]

ok, well i know that it's not the alternator that keeps the car running.... the alternator isn't charging!!

sooo.... today i'm taking out the alternator (new) and taking it to autozone to have them test it. if it tests bad, then obviously i'm going to have them replace it.

if the alternator tests good, then it's obviously a wiring problem. i triple checked my diode and it's fine. however, i did disconnect the white/red wire that's attached to the alternator and replaced it with a 4AWG wire running back to the battery cutoff switch. would this cause one of these problems? (edit: if i read correctly, that white/red wire goes through the diode, correct? if that's the case, how do i do the 4AWG wire to the back of the car?)

if anyone in/around san diego is good with wiring/electrical and wants to come help me out, i'll offer beer and maybe car parts!