Jump to content
SAU Community

Batteries Going Flat.

Raul

By Raul,
in General Maintenance

 Share

Recommended Posts

Raul Explorer

Raul

Posted
Posted

Hey,

posted here about a week ago about my alarm playing up. Turned out it was a dead battery, so i then got a new battery and has been all good until now (a week later). This has lead me to suspect that something is running my batery flat! couldit be that the workshop that installed my alarm installed it wrong and may that be the cause of my batteries being sucked dry? Before the alarm was installed it was fine.

Also it has been suggested that the alternator may be the problem, however wouldnt their be a dash light going off if this was the case?

Cheers

Link to comment
https://www.sau.com.au/forums/topic/148508-batteries-going-flat/
Share on other sites
wilch Grand Master

wilch

Posted
Posted

No dash light for the alternator.

To test if the alternator is stuffed:

- Grab a multimeter. Put it across the positive and negative terminals on your battery with the car off. Make sure it reads about 12v.

- Turn the engine on. Do the same thing. Put the multimeter across the positive and negative terminals on your battery. It should now read about 14v give or take a 0.5v or so.

- If it still reads the same as when the engine was off then your alternator is dead.

The other thing that could be wrong is that your battery is on it's last legs. How old is it?

If it's not the alternator or the battery then it has to be the alarm install. In which case you should take it back and get them to check what they've done. It could be something as simple as an incorrect ground.

I had an internal piezo screamer installed in my car that I had to remove due to it constantly draining my battery. It was a case of the alarm sending a ground signal instead of sending 12v to set the siren off. With the piezo screamer not being grounded properly and being connected to 12v, this meant that the battery was being drained constantly.

blind_elk Grand Master

blind_elk

Posted
Posted
- Turn the engine on. Do the same thing. Put the multimeter across the positive and negative terminals on your battery. It should now read about 14v give or take a 0.5v or so.
Rev the engine to around 2k. If the volts increase with revs, the regulator is cooked, and will result in your battery being overcharged. Overcharging will kill it.
Raul Explorer

Raul

Posted
  • Author
Posted

Jsut got my hands onm a multimeter, and the battery was reading 6 so i jump started it and it read up to 14v constant. Even when reving the engine it was constantly on 14v.

So can i assume that my alarm that was installed at one of SA's reputable wokshops has been installed incorrectly? If so i wont be happy as i have had so many headaches with this alarm its not funny.

Cheers for the replies guys

blind_elk Grand Master

blind_elk

Posted
Posted
14v for a running motor is fine. It will go down to around 12v though after a short time when running.

Check the alternator output as wilch and blind elk said. It shouldnt cost too much to have it rebuilt, or just buy a new one.

Switch everything off. Switch the multimeter to amps, remove the +ve cable, and measure the amps between +ve battery terminal and the +ve cable. Reconnect battery. Then remove each fuse in turn, and measure if any amps across each fuse slot - that will tell you which circuit is drawing the current that is killing the battery.
Raul Explorer

Raul

Posted
  • Author
Posted (edited)

Hey,

Just to clarify ont he multimeter where should i be leaving teh knob to test the fuses?

Well i had the knob turned on the icon with an arrow and a '+' sign nextg to it and it gave me a reading of around 5-6v between the batterys positive terminal and positive cable. Then in the fuse panel under the drivers side dash, the fuses under ign had a reading of around 4-5v.

Any suggestions? Basically i want to pinpoint where the power is getting sucked as i want to know whether or not it was the alarms installation fault or not.

Cheers

Edited by Raul
blind_elk Grand Master

blind_elk

Posted
Posted

You are measuring VOLTS, you need to measure AMPS (ie current). Volts are measured in parallel with the device you are testing, amps are measure in series.

It will probably vary with the design of the multimeter you have - mine has A (makes sense) near the various scale settings.

And you only need to check the fuses if you find a significant current flowing from the battery.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • GTSBoy
      Cas issue

      By GTSBoy · Posted

      The wideband reading is meaningless if it's not running. Why are you using shitty old sidefeeds on any engine, let alone a Neo? What manifold and fuel rail are you using to achieve that? Beyond that, can't help you with AEM stuff as I've never been their ECU/CAS combo.
    • Duncan
      RB26DETT Sketchy boost mod?

      By Duncan · Posted

      Manual boost controllers (where a little of the boost was bled off) were quite common back in the day, because they were cheap and easy. Generally they had a manual adjustment screw rather than being fixed like yours. Down side is they always bleed boost, not just when you want them to so an electronic boost controller that uses a solenoid will have less lag.
    • nash47
      Cas issue

      By nash47 · Posted

      Hello , im new here and i have A31 home build  RB25det neo stock eng / turbo  aem ems 2 blue connector  aem 3.5 map aem cas disk aem wideband connected to ecu  355 lph pump 550 nismo yellow injectors side feed aftermarket regulator  and won’t start with base aem tuner basic tune eventually flipped cas 180 degree so it triggers on correct stroke not in exhaust cycle  Now it won’t start Wideband reads 10 and 11 at lowest fuel setting  and will share calibrations soon for aem tuner i think something is wrong in aem tuner    please if you have any information, am very grateful         
    • nxh
      R34 4 door side skirt identification

      By nxh · Posted

      Legend. I ended up finding the facebook account of the owner of the first car i sent but sadly he deactivated the account. I think you’re right in saying it’s some sort of well done custom job. Really appreciate your help anyways.
    • GTSBoy
      boost source Size Garrett gt28 gen2

      By GTSBoy · Posted

      Totally equivalent. Stock often goes from the comp cover because that's where the actuator is also installed and the factory needs 2" of hose to make the connection - and it comes as a pre-assembled unit. They totally have a boost reference from somewhere between the turbo and the throttle(s). Oh, jeez. Just do it in M12 then. We don't actually care that much. I would expect any such AN converter fitting to rely on an o-ring or some other seal onto a flat surface under the flange of the hex**, because bolt threads are no intended to provide a pressure seal. unlike..... pipe threads. **which also requires a suitably flat and smooth surface on the turbo's boss to provide the seal.
×
×
  • Create New...