12 Volt Power Supply

[zerow]

I am confident in the harnesses that are going into the sedan. I have one more harness to physically check for damage, the interior main harness. I know there are some (ahem) wiring snafus that I *might* have done in haste when she and I were in high school.

 

I don't want to buy a new battery to keep running it down making sure the lights work and relays are functional in their correctly installed positions.

 

So, my question: Is there something I can rig up to check circuits while on the car? A Ratsun method preferably, but I am open to suggestions. Let me know! :thumbup:

[izzo]

12V battery charger, make sure you protect the wires though and alligator grips. dont want that shit touching metal :)

[hang_510]

dont want that shit touching metal :)

or each other!

 

 

a wall type (low current & 12VDC) charger will also work.

[thisismatt]

Most wall chargers/adapters are only a few hundred milliamps up to maybe a couple amps, and car battery chargers may only be a couple amps. Headlights, parking/blinker lights, heater blower motor, etc etc all use more than a couple amps. There isn't really a good cost effective 12v power source that can supply the current for 12v automotive systems draw.

[izzo]

Think it would still be enough to at least test the system? the lights and stuff should at least come on, even if dim no?

[thisismatt]

Probably burn up your power supply

[hang_510]

Think it would still be enough to at least test the system?

my power supply idea is to check voltage, not operate the entire system!

[thisismatt]

my power supply idea is to check voltage, not operate the entire system!

Checking voltage of what? If you're just checking continuity then your ohm meter already has a power source (its own battery)

[hang_510]

:hmm: check voltage :confused:

 

:no:

 

 

:blush: i meant supply voltage for the operation of an individual system, & def not capable of replacing the battery.

[Icehouse]

I used to have a cool jumper box that had a built in circuit breaker. It was bad ass for what you are doing. Bad shit happened the breaker would flip. But the tweekers got it a while back :( Damn they don't give up. So if you know of anyone who has one. Mine was to shitty to start a car but it was awesome for checking circuits. Just saying.

[elmerfudpucker]

Most good battery chargers have their own protective auto reseting circut breaker. As long as you get 10 to 15 amp charge at the most, not the startup setting where it dumps some amps, or the 2 mayby 5 amp trickle, you should be fine. Find a good charger and test away.

[I'm BLUE]

IDK just throwing out there , a long jumper wire from another car ( fusebox ) ? :lol:

[freekwonder]

I grabbed an inexpensive lawn/tractor batter and an inexpensive charger from Walmart. Been enought to test out all my wiring.

[zerow]

These are all great ideas! I had one, but it may be a long shot: The power supply for a computer has 12 VDC at the connectors for harddrives, CD/DVD ROMs and such. Should have enough to do what I need.

 

Remember, I am NOT starting the car with it, just checking lights and relays. If I hear it 'click', I move on. If the light illuminates, I move on (and check it off the list...)

[datzenmike]

You want somewhere around 5 amps (or more is ok too) like a battery charger. If you don't have one they are good to have anyway for cold weather. Less than that may not light up things like multiple lights in the dash or tail/running or brake lights.

[flyerdan]

An old power supply from a computer will have around 5 amps at 12 volts. Takes a bit of sorting because there is +5, -5, +12 and -12 circuits but old computer power supplies are plentiful and free, and if it gets post toastied, no big loss.

[zerow]

You want somewhere around 5 amps (or more is ok too) like a battery charger. If you don't have one they are good to have anyway for cold weather. Less than that may not light up things like multiple lights in the dash or tail/running or brake lights.

My thought exactly. Just testing lights and circuits.

 

I don't want to buy a new battery, and that is because of another major hitch: BMW projector lights. I will need (what I think) a Chrysler/Plymouth/Dodge battery from a Cirrus, one that is fender mount, to avoid hitting the backs of the depp projector lights. I. Good Cranking Amps in a different sized package.