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battery gremlins

  • Thread starter Thread starter tweet66
  • Start date Start date May 24, 2005
T

tweet66

Founding Member
May 19, 2001
589
0
17
Pennsauken, NJ
May 24, 2005
#1
  • May 24, 2005
  • #1
I need some ideas? My daughter's 65 4 dr Falcon keeps killing the battery after sitting for a few days. at first I thought it might be bad but the load tester says its actually in really good shape. So I disconnect the pos. cable and put a meter in line. Lo and behold I'm drawing 3.5 volts I pulled each fuse to see if I could identify the offending circuit, got a 2 volt drp from the dome light fuse, but even with all the fuses and the radio pwer and memory disconnected I still pull 1.5 volts or slightly more????? Any ideas? One other thing when I found the 2 volts on the dome circuit I happened to hit the door switch & brake pedal, which gave an immediate 12 volt draw, but when I let off the pedal or pushed in the button the voltage took a minute or two to return to zero. Shouldn't it drop immediately. Help :?
 
B

BB1966

New Member
Dec 1, 2004
297
1
0
Beaufort , NC USA!!!!
May 24, 2005
#2
  • May 24, 2005
  • #2
Does the alternator get hot while the battery is hooked up but the engine not running??? If so that is the problem,not to common on the older style alts but still may be it.
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
May 24, 2005
#3
  • May 24, 2005
  • #3
what about a sticking regulator,my buddiy's 65 Vert did it all the time.
 
T

tweet66

Founding Member
May 19, 2001
589
0
17
Pennsauken, NJ
May 24, 2005
#4
  • May 24, 2005
  • #4
BB1966, no the alt doesn't get hot at all.

iskwezm, never thought about the VR. I have two new VR I try switching one in and see if that make a difference.
 
T

tweet66

Founding Member
May 19, 2001
589
0
17
Pennsauken, NJ
May 29, 2005
#5
  • May 29, 2005
  • #5
update and more?

Alright I finally got some time to get back to this thing, so I tested the charging circuit this evening. With the pos. cable disconnected from the battery and the meter on the pos. post of the battery, AND every wire disconnected form the terminal on the selonoid, I checked each terminal on the VR plug. Here's what I got:
F=12 volts (shouldn't that be dead?)
S=jumps to .5 volt then drop off the scale
A=jumps to 2.5 volts the drops to a constant .35 volts
I= 12 volts (I would expect this to be dead too since it goes to the acc. side of the ign. switch?)
I also check from the pos. battery terminal to the black-yellow wire running to the fuse panel and ign switch and had a 11.5 volts draw. Seems to me like the ignition switch might be suspect. Any thought and TIA.
 
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