2005 Mustang GT Dead Battery
09-15-2014, 11:39 PM
#151
4th Gear Member
Join Date: Nov 2008
Location: California
Posts: 1,495
I'm still here!
Random questions, thoughts, comments, whatever:
Are you driving the car right before you begin your testing? You need to activate various modules by driving (Ford suggests at least five minutes at no less than 35 mph).
Are you then letting the car sit with the key off for at least 40 minutes before taking your current readings? Some circuits can take that long to power down.
It wasn't clear to me whether you removed all of the fuses and only the ones you mentioned caused a current drop. You're going to need to check all of them.
The TOTAL parasitic draw should not exceed 50 mA. If you have several circuits that are EACH drawing 30 mA, then the total is more than 50 mA.
Don't forget that not all circuits are fused.
Check for bad grounds. Edit: Also check the positive battery cable for good connections, and also for corrosion. The bad battery was probably offgassing a lot. Corrosion could be hiding in the cable, close to the battery end and a bit under the insulation.
An internal short in the alternator could cause excess parasitic draw.
Good luck!
Random questions, thoughts, comments, whatever:
Are you driving the car right before you begin your testing? You need to activate various modules by driving (Ford suggests at least five minutes at no less than 35 mph).
Are you then letting the car sit with the key off for at least 40 minutes before taking your current readings? Some circuits can take that long to power down.
It wasn't clear to me whether you removed all of the fuses and only the ones you mentioned caused a current drop. You're going to need to check all of them.
The TOTAL parasitic draw should not exceed 50 mA. If you have several circuits that are EACH drawing 30 mA, then the total is more than 50 mA.
Don't forget that not all circuits are fused.
Check for bad grounds. Edit: Also check the positive battery cable for good connections, and also for corrosion. The bad battery was probably offgassing a lot. Corrosion could be hiding in the cable, close to the battery end and a bit under the insulation.
An internal short in the alternator could cause excess parasitic draw.
Good luck!
Last edited by Art161; 09-16-2014 at 12:20 AM. Reason: Additional thought
09-16-2014, 09:49 AM
#152
Join Date: Oct 2013
Location: NC
Posts: 44
Hi!
Thanks again for another informed response. Yes, I did pull ALL of the circuit breakers AND fuses. No, I didn't drive the car beforehand. Battery cables look good and all obvious ground connections look good too.
I need to go to the store later and will retest per your recommendations.
I need to go to the store later and will retest per your recommendations.
I'm still here!
Random questions, thoughts, comments, whatever:
Are you driving the car right before you begin your testing? You need to activate various modules by driving (Ford suggests at least five minutes at no less than 35 mph).
Are you then letting the car sit with the key off for at least 40 minutes before taking your current readings? Some circuits can take that long to power down.
It wasn't clear to me whether you removed all of the fuses and only the ones you mentioned caused a current drop. You're going to need to check all of them.
The TOTAL parasitic draw should not exceed 50 mA. If you have several circuits that are EACH drawing 30 mA, then the total is more than 50 mA.
Don't forget that not all circuits are fused.
Check for bad grounds. Edit: Also check the positive battery cable for good connections, and also for corrosion. The bad battery was probably offgassing a lot. Corrosion could be hiding in the cable, close to the battery end and a bit under the insulation.
An internal short in the alternator could cause excess parasitic draw.
Good luck!
Random questions, thoughts, comments, whatever:
Are you driving the car right before you begin your testing? You need to activate various modules by driving (Ford suggests at least five minutes at no less than 35 mph).
Are you then letting the car sit with the key off for at least 40 minutes before taking your current readings? Some circuits can take that long to power down.
It wasn't clear to me whether you removed all of the fuses and only the ones you mentioned caused a current drop. You're going to need to check all of them.
The TOTAL parasitic draw should not exceed 50 mA. If you have several circuits that are EACH drawing 30 mA, then the total is more than 50 mA.
Don't forget that not all circuits are fused.
Check for bad grounds. Edit: Also check the positive battery cable for good connections, and also for corrosion. The bad battery was probably offgassing a lot. Corrosion could be hiding in the cable, close to the battery end and a bit under the insulation.
An internal short in the alternator could cause excess parasitic draw.
Good luck!
09-16-2014, 04:55 PM
#153
Join Date: Oct 2013
Location: NC
Posts: 44
Tested again.
Thanks again for another informed response. Yes, I did pull ALL of the circuit breakers AND fuses. No, I didn't drive the car beforehand. Battery cables look good and all obvious ground connections look good too.
I need to go to the store later and will retest per your recommendations.
I need to go to the store later and will retest per your recommendations.
Just retested per your recommendations and came up with the following:
With the selector set at 10a, the meter starts at a rapidly fluctuating 1.65 and moves down to a non-fluctuating .10. When I turn the selector to 200m it reads 1.0 and when I turn the selector to 20m it reads .10. I know .1a is 100 milliamps but don't know what to make of the rest of it.
A recommendation in another forum stated to unplug the alternator but I don't see an easy way to do this as it sits up under the intake manifold!
All thoughts welcome.
09-16-2014, 07:13 PM
#154
Join Date: Oct 2013
Location: NC
Posts: 44
Update:
Art161,
Just retested per your recommendations and came up with the following:
With the selector set at 10a, the meter starts at a rapidly fluctuating 1.65 and moves down to a non-fluctuating .10. When I turn the selector to 200m it reads 1.0 and when I turn the selector to 20m it reads .10. I know .1a is 100 milliamps but don't know what to make of the rest of it.
A recommendation in another forum stated to unplug the alternator but I don't see an easy way to do this as it sits up under the intake manifold!
All thoughts welcome.
Just retested per your recommendations and came up with the following:
With the selector set at 10a, the meter starts at a rapidly fluctuating 1.65 and moves down to a non-fluctuating .10. When I turn the selector to 200m it reads 1.0 and when I turn the selector to 20m it reads .10. I know .1a is 100 milliamps but don't know what to make of the rest of it.
A recommendation in another forum stated to unplug the alternator but I don't see an easy way to do this as it sits up under the intake manifold!
All thoughts welcome.
Update:
Meter actually fluctuated between .09a and .1a for about 40-45 minutes before dropping to zero in all amp and all three ma settings. Thinking this means I have no 'parasitic draw' issue? Reconnected meter twice to verify.
I've been sloppy in the past about connecting the battery cables - could this be the cause? Love this car - grinned the whole time I drove it today as well as everyday in my possession.
09-16-2014, 11:03 PM
#155
4th Gear Member
Join Date: Nov 2008
Location: California
Posts: 1,495
I've never heard before that these cars have 0 mA parasitic draw. There are many circuits that are powered down, but still have some current draw. The lowest I've heard is about 20mA. Mine was measured as 40 mA.
Can you try a different meter for your measurements?
Can you try a different meter for your measurements?
09-17-2014, 07:48 AM
#156
Join Date: Oct 2013
Location: NC
Posts: 44
Meter timed out?
No other meter readily available. Thinking my meter timed out? Thinking there should be some draw obviously. I'll go with the last known reading: 100ma. Looking for an easy way to check the alternator without removing the intake manifold.
11-08-2014, 07:19 AM
#157
Join Date: Oct 2013
Location: NC
Posts: 44
Update
Update: Meter probe cable was plugged into the incorrect receptacle. Final meter reading after about 40 minutes was 30mA. Reconnected battery, set clock and have had no 'dead battery issues since - car sits for up to 4 weeks at a time. Still wondering if an incorrect battery hookup sequence causes something (smart module?) not to power down correctly and kill the battery over time?
me draw obviously. I'll go with the last known reading: 100ma. Looking for an easy way to check the alternator without removing the intake manifold.
01-20-2016, 02:19 PM
#158
Join Date: Oct 2013
Location: NC
Posts: 44
Update: Meter probe cable was plugged into the incorrect receptacle. Final meter reading after about 40 minutes was 30mA. Reconnected battery, set clock and have had no 'dead battery issues since - car sits for up to 4 weeks at a time. Still wondering if an incorrect battery hookup sequence causes something (smart module?) not to power down correctly and kill the battery over time?
02-17-2016, 10:16 AM
#159
Join Date: Feb 2016
Location: nj
Posts: 3
dead battery locked out key doesnt work
hi I have a 2006 mustang gt the battery is dead and the car is locked. is there anyway in the car other than using a locksmith??? we can get the trunk opened but the key does not work in the drivers door. it must have been changed before bought car. is there a trick to getting in?
any input is appreciated. would a slim jim tool work?
any input is appreciated. would a slim jim tool work?
02-17-2016, 07:30 PM
#160
5th Gear Member
Join Date: Jun 2005
Location:
Posts: 3,319
I have an '06 GT and I don't have any of these problems. My wife & I go on a 2 week vacation every year (going back to Hawaii this summer) and have never had any battery problems letting it sit there for 2 weeks. I never do anything special when I leave, just pull her into the garage and she starts fine when I get back.
I am guessing if you have a good battery and a good alternator, you shouldn't have any problems, or maybe I'm just lucky.
I am guessing if you have a good battery and a good alternator, you shouldn't have any problems, or maybe I'm just lucky.