Newer Battery-Dead Now-Must Have Drain-or POS Battery

[joshnjulie1]

Read up on the posts but still feel ignorant as to how I go about testing my system for a drain.

Had the battery on a trickle charger and have not hooked it back up yet. I will wait for advise before proceeding.

So, how do I go about using a multimeter (not that good at using one as it is) and where do I put the leads to determine current draw and what am I looking for?
Do I unhook the negative cable only?

EB has a new Centech wiring harness.
Have not had this issue prior to replacing the battery (could be battery but not sure how to tell)

No aftemarket radio or anything aftermarket to draw power.

Appreciate the help in advance.

 

[nvrstuk]

To test for current draw with a multimeter you must make sure that it is rated for whatever amperage you might be drawing... my .02 is, I wouldn't use it unless it is rated for 10amps or more. Then you hook it up in line to the positive cable.

If you don't hook up the meter correctly, you will fry it in an instant!

 

[joshnjulie1]

Update: Need knowledge
Battery at hook up=11.9
Fired and running = 11.7

does that mean my alternator is fried?

 

[Viperwolf1]

Update: Need knowledge
Battery at hook up=11.9
Fired and running = 11.7

does that mean my alternator is fried?

That's a good indication it isn't working. Is it the same at higher running speeds? Might look at the alternator wiring to make sure its right.

 

[nvrstuk]

Just gotta ask this since I'm trying to see if others are having the same issues with alternators dying...

Couple questions:

1 Did your battery get drained, then you jump started it to get it going again?

2 Are you running a 3G battery?

3 where did you buy the alternator? Is it Motorcraft or rebuilt from Napa or Autozone?

 

[pbwcr]

Update: Need knowledge
Battery at hook up=11.9
Fired and running = 11.7

does that mean my alternator is fried?

Batt was dead in the beginning. And either the alt or reg are also defective.
Charge the batt and measure the volts again.
Who's batt? What alt/reg?
PaulW

 

[Slednut10]

I had the same type of issue last year with my 78 F250. New battery, and it was charging. Checked everything for current drain but didn't find one. Turned out to be the external regulator. I got lucky as I left it unplugged after chasing wires and after a few days I went back to try again and the battery had not drained.

 

[joshnjulie1]

Same reading at any RPM.
Did the 'ol pull the positive while running and she shut off in an instant.
Alternator must be fried.

Why though did I get no other indication previously when driving? I never had a hard start or slow cranking start giving me any indication.

I guess it could have been just good luck that it died in my garage and not on the road.

 

[joshnjulie1]

I have never replaced the alternator. not sure how old or by who.

 

[joshnjulie1]

Update;
Started reading the maunal for the Centech wiring harness to get an idea of what it could be since I replaced the alternator and the voltage regulator, and theh alternator was still not charging the battery.

Upon reading, it stated that as the VR regulates the V from the alternator, and is done so by the green 'reg' wiring, I followed it back to the fuse panel.
10A fuse was blown.
Replaced it and it was working as it should.

Most expensive fuse...But...at least I have a new alternator and VR now too.