Safe to run harness off of battery charger?

[Jaguar_5]

I have abit of a weird question...

Is it ok to use the output of a low amperage battery charger connected to the positive of the main body harness (where it would be connected to positive from the battery obviously) and the negative to a chassis ground, just so I can test out my gauges, and maybe a few other accessories?

Should I also connect it to the engine block? Or is this just a bad idea altogether?

I've been wiring all my gauges up and would like to test them before getting a battery and having things put back together

 

[tbcmorris]

I would say you will be fine. If it was a new bmw or something with a million body conrtol modules I would say no. Take the battercables and attach them to the clamps on the chager.

 

[CRE]

Most chargers won't even run in that scenario. Either pick up a 12v power supply or borrow a battery would be my suggestion.

 

[Jaguar_5]

But if it does run it will be ok?

If I risk running any damage I'll just wait until I'm ready to buy a battery

 

[JonoTurbo]

There's no reason it would harm anything as long as you didn't start the engine.

 

[Jaguar_5]

lol I'll definitely be waiting until I have a battery before I try and start the engine :biglaugh:

 

[gofastgeorge]

I sure would NOT...........

Battery chargers are Very 'dirty' as far as power output.
They induce a lot of AC ripple into the DC.
Many newer components, like S-AFCs, memory gauges, etc., won't take this.
And it is the worst thing you can subject your ECU to.....

Use a power supply, or a battery.

 

[Jaguar_5]

My ECU isn't plugged in... I'll just run some jumper cables from another car or something

Thats the kind of response i was looking for, thanks!

So does this mean when using a battery charger you should disconnect it from the car first? Or as long as everything is turned off it's ok?

 

[CRE]

So does this mean when using a battery charger you should disconnect it from the car first? Or as long as everything is turned off it's ok?

Depends on the charger and the amount of planning behind it.

It's a good idea to disconnect the battery before charging. A lot of chargers advertise that they're safe and may be used while the battery is connected, but keep in mind that they may not be proofed against large surges. If you're using a manual charger you must disconnect the battery first.

Only charge the battery in a well ventilated location. Even if it is sealed. Charging batteries produce gases which are highly flammable. Even sealed batteries have vents, just in case. If these open you definitely want to be sure the gas isn't lingering.

Keep a frequent eye on your charger and battery while charging.

Most important.... read the manual!