DesiDez

Ok here's my situation: 94 del sol si with a b18c. My battery is completely dead. I jump start the car and let it run for 10 minutes, then turn off the car. After a couple of hours, the cars won't turn on. So i've been searching HT and found several items to check.
1) battery
2) alternator
3) grounds
4) parasitic drain

I decided to check for a parasitic drain first. This is what I did. I've never done before either. I unhooked the neg. terminal from the battery. I connected my volt/amp meter to the terminal and the battery post, and set the meter to 200mA. My first reading is 4.5. I read that if it's above .20, then I have a parasitic drain.

I then start pulling fuses under the hood, and keep testing for a parasitic drain. When I pull the 7.5 backup fuse, my meter reads 0.0 So is this my problem? Am I even doing this test correctly? If I am, what should i do next to fix this problem? thanks.

DesiDez

anybody?

1992Si

Did you post this in the Tech/Misc forum too.

This a question not many could answer.

Good Luck.
Hey I assume you've had the battery checked, most auto part stores will test it for free.

Luserkid

Never heard of a Parasitic drain test, just regular drain test. What i normally check is if the alternator is powering the batt or not, or if its giving off power on its own. Start the car and check the voltage on the alternator post. Should be 14v. Next go to the fuse box and test the white wire and make sure thats getting 14v, then the thick wire next to it (should be 14v) and finally the batt. If theres a break then fix that.

After all the comes back check to see if your batt is holding a charge. Charge it up and take a reading. Take everything off for a half hour to an hour and check it again. If it drops then your batt. is toast.

Then if that all turns out ok retrace your steps back before this started happening, have you installed anything electrical? Check your wiring on whatever you installed.

DesiDez

Luserkid, after I jump start the car. Do i have to take any of the battery terminals off?

Or do i just connect my meter to the negative battery post (w/ terminal still connected) and then to the altenator post?

Echo7847

5-15ma is the expected range of parasitic draw for your vehicle.

When you measured did you start @ 10a and work your way down to 200ma to get the correct reading? Does your meter have an auto range function?

Luserkid

If the car always needs a jump to start i would take the batt in to autozone for a quick drain test on that. But what you do, jump the batt. Take the jumpers off and leave the car as it is (with all its connectors). Then do the test i told you. But if you need a jump everytime im going with dead batt now.

DesiDez

I got a cheap tester from advanced auto. It doesn't have have a 10mA. It has 20mA and 200mA. I think I started with 200 first.

Don't know if it has an auto range function. It has a turning dial.

DesiDez

luserkid,

I started your test. I checked the alternator and the two wires and got 14.5v. So I think that's all good, right?

I'll charge up the battery next.

1992Si

How old is the battery ?

7 years is about max.

Luserkid

Did you check the voltage all the way back to the batt. This test helps you figure out if theres any broken wire from the alt to the batt to allow it to charge. If your line is good all the way to the fuse box but isnt good to the batt then check your wire or the 80A batt fuse.

But more and more i read the thread it shows you have a simple dead batt.

DesiDez

I'd figure it might just be the battery itself. But I just wanted to make sure that everything else was fine before I spent $50 on a new battery when already i really was to tighten up the wires at the fuse box for example.

I don't know how old the battery is. I bought it the car off a kid who didn't seem like he took of it that well.

I'll the car sit for a couple of hours and if it doesn't start again, I'll head off the advance auto.

Thanks, fellas for the help.

95dxsir2

yes, you are doing the test right. check what circuits are on that fuse. i don't have the wiring diagram. hopefully u have a manual. keep going.

DesiDez

95dxsir2, i did that test again, and now i'm getting a 0 reading. I have no clue what i did differently to get that except that i did pull the 7.5 fuse out. it wansn't blown though

95dxsir2

did you do the test again with the fuse out or in?

stock_honda_coupe

Keep in mind when doing a parasetic draw test, it can take the computer 20 mins or more to "go to sleep". When you do this test, use clips or something so your multimeter leads stay connected and just let it sit for like 30 mins. I think with a 50 milli amp draw, your battery will last for just under a week. The normal rule of thumb though is 20 milli amps or less.

DesiDez

bump. I've isolated the problem to the 7.5 backup fuse under hood, but what exactly does this control. My chilton's manual isn't too helpful. Thanks.

Padawan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DesiDez &raquo;</TD></TR><TR><TD CLASS="quote">bump. I've isolated the problem to the 7.5 backup fuse under hood, but what exactly does this control. My chilton's manual isn't too helpful. Thanks.</TD></TR></TABLE>

If I'm not mistaken, it provides minimal back-up power to the ECU and radio while the ignition is switched off.

stock_honda_coupe

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Padawan &raquo;</TD></TR><TR><TD CLASS="quote">

If I'm not mistaken, it provides minimal back-up power to the ECU and radio while the ignition is switched off. </TD></TR></TABLE>

And the dash clock. Basicaly it goes to every thing that has a memory.