Hooking up battery to newly rewired car

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plumkrazee70

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I just finished rewiring my car with the EZ wiring kit and the instructions say: connect the positive battery cable before connecting the negative cable you should check for current draw. This can be done easily with a test light connected between the negative battery post and the negative battery cable. No light equals no draw, if you have no draw or just a really dim light it is safe to connect the negative battery cable and start checking the system.

However, I have a bright light. I checked it with my meter and I have 12V. I am not sure I understand, though. Won't I always have that due to a few circuits being hot all the time ?
 
When I did mine after restore, I took my meter in DC amp mode and series it in on first touch. I Was shocked to see the load a couple lamps created. Closed all the doors and everything I thought would be powered. Still had an issue with brake switch adjustment. Got the load to zero then felt happy! The rest is bliss!
 
You can always check ohms with your meter between the battery cables and do the E=IxR calc if R “resistance” is not equal to zero!
 
When I did mine after restore, I took my meter in DC amp mode and series it in on first touch. I Was shocked to see the load a couple lamps created. Closed all the doors and everything I thought would be powered. Still had an issue with brake switch adjustment. Got the load to zero then felt happy! The rest is bliss!

I am not sure I understand. The dome isn't hooked up. I don't have the door jam switches yet. So that wire is just capped. The ignition and turn signal switches are unplugged (made no difference) There isn't anything left, that I can think of.
I started pulling fuses and nothing changed, although I didn't remove them all.
 
It can be lots of things. Check with your meter between battery cables and what is the OHM resistance?

Ohms law, google it for all the calcs. It will give you the amp current based on 12.5 or 13v as E. If you are under .5 amps I would not be concerned for start up. you can better determine E by reading voltage on your battery in current state of charge. Keep looking and unplug as needed. Not familiar with the EZ wiring setup as I prefer the factory wiring.
 
No, positive to negative cable.
 
Test lights can be real handy but a good DVM Meter is a must.
 
Nevermind. I was over thinking it. Of course I would have 12v when hooking the meter in series. Essentially just used the meter as the batter cable.

I went ahead and hook the negative up to the battery, and have power Woohoo! The marker lights did however stay on (regardless of HL switch position.) I quickly figured I have the turn signal switch wired in correctly. The lights are on all time but will go out if the hazards switch is pulled.
 
Nevermind. I was over thinking it. Of course I would have 12v when hooking the meter in series. Essentially just used the meter as the batter cable.

I went ahead and hook the negative up to the battery, and have power Woohoo! The marker lights did however stay on (regardless of HL switch position.) I quickly figured I have the turn signal switch wired in correctly. The lights are on all time but will go out if the hazards switch is pulled.

if so guess you found that draw, and congrats for your piece of mind! Test lights give that quick look but a meter is a must though.
 
Sorry I am late to this party HERE IS HOW you do this---to prevent some mistake from smoking something important

FIRST do NOT just hook a multimeter in current (amps) up because if you have a "heavy" short it can damage some meters. Better meters, generally, Fluke, have fuse protection but those fuses are EXPENSIVE, approaching 10 bucks last I checked.

So, HOW? Easy, really

You want a big wattage 12V lamp. If possible, you want "a selection." Easy / cheap way is to use an old tail/ stop lamp socket, with an 1157 bulb. This bulb of course has two different wattage filaments. Best thing, you can wire this "tool" several ways for different jobs

For highest wattage, twist both socket wire leads together and use the shell for the other connection.

Connect either the shell or the wire leads, does not matter, to a known good ground point on the car. Connect the other terminal to your battery NEG post. This will create a series test lamp that NO MATTER HOW LARGE the short is, it will only cause the lamp to light

If the light does not light, or only lights dimly, you can assume that you at least do not have a heavy short

If it glows some, you can assume there is a load turned on in the car, such as the dome, tail, etc.

AT THIS POINT, if the lamp is less than "full brilliance" you can assume that it is safe to hook your 10A multimeter and determine how large the draw is.

Alternatively you can connect a SMALLER test lamp to "judge" the draw. Try your small 12V probe lamp. If that is "full bright" go back to your tail/ stop tool. Try using the shell, and the tail wire. This is a small wattage bulb and if it glows dim, you can have a smaller draw, like maybe the dome lalmp, etc.
 
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