Starting issues after dead battery
6/14/18, 07:09 PM
#1
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Starting issues after dead battery
Bought my Mustang in February 2015 and recently had to replace the battery because I seldom drive it. 2,400 miles on it. When the battery first went down it would take a charge but for a while I always had trouble getting the push start to work. It would indicate "power mode" alarm are something like that. After a number of attempts it would eventually start and usually not cause a problem until the battery died again. Then the same thing all over again. it was almost like the computer had to relearn the battery was ok. I finally replaced the battery and all was good until last week when the battery read about 11.5 volts and same push button start problem. Is this normal operating procedure, I cant find any information in the manual. By the way the battery recharged fine and once I got it started it has worked as it should. Forgot to add any comments is appreciated.
Last edited by legirons; 6/15/18 at 10:17 AM. Reason: Add comment
6/15/18, 02:33 PM
#3
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These modern cars always have a small drain (usually milliamps) on the battery to maintain the various electrical systems that need a little power even when they are turned off. Over a long period of time, this will drain the battery. So you either need to drive it more often (which would be my choice!) or use a battery charger or tender.
You could have it checked to make sure the drain is in the normal range, but my SWAG right now is that it is "normal"
You could have it checked to make sure the drain is in the normal range, but my SWAG right now is that it is "normal"
6/15/18, 02:53 PM
#4
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Sometimes might go two or three weeks without driving it. I am just to protective I think. It has never had food in it and I will not park it anywhere that I don’t have plenty of room. Drove it today and some nut almost caused a wreck right in front of me. Yes I know I should enjoy the car if I am going to keep it.
Last edited by legirons; 6/15/18 at 02:54 PM. Reason: Grammer
6/15/18, 03:25 PM
#5
Bullitt Member
Have you installed any accessories to it? Anything at all? Cables left plugged in? Long shot as these cars are pretty loaded any more. But the issue sounds similar to what happened to my '06 right after I got it.
I had a stereo installation place install an aux line to the radio. And if I didn't drive the car for 2 days, the 3rd day the battery would be completely dead. Took to dealer, they replaced the battery twice. After the third time, they tracked the issue to the improperly installed device connected to my radio. They left the dash in a pile, charged me $250, and told me to take it back to the place that installed the aux port.
After they installed a new one, the battery was fine.
Not sure what kind of normal drain would happen in two weeks time for a car. I know my Triumph may or may not start if I don't ride it for two weeks.
I had a stereo installation place install an aux line to the radio. And if I didn't drive the car for 2 days, the 3rd day the battery would be completely dead. Took to dealer, they replaced the battery twice. After the third time, they tracked the issue to the improperly installed device connected to my radio. They left the dash in a pile, charged me $250, and told me to take it back to the place that installed the aux port.
After they installed a new one, the battery was fine.
Not sure what kind of normal drain would happen in two weeks time for a car. I know my Triumph may or may not start if I don't ride it for two weeks.
6/15/18, 04:47 PM
#6
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The car is just like it was when it left the factory. I am not too concerned with the drain on the battery because I think it is normal. My issue is when I allow the battery to drop below 12v I have trouble getting the start button to work normal for the first or second start. This is after I have charged the battery. From what I find in the owners manual I think it has to do with the battery management system on the car. Seems when the voltage drops below a certain point the system automatically shuts down some of the battery load. Just seems to me that after I recharge the battery it should reset to normal.
6/17/18, 12:43 PM
#7
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Just grab you a good battery maintainer, and that will cure your troubles my friend. I have to keep my plastic Chevrolet on life support all of the time because of the battery drain from the on board electronics.
6/30/18, 10:16 AM
#8
Legacy TMS Member
I have a Battery Tender solar charger on the rear deck of my 05 GT. I had the same issue of having a dead battery if I didn't drive it for a couple of days and once I put the solar charger in I haven't had the problem since.
7/4/18, 11:57 AM
#9
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The Mustang finally got to the point where the start button would not engage the starter. I tried everything I could think of ie tested the battery, different key fob all combinations of push clutch, push brake etc. finally gave up and had it towed to the dealer late yesterday. Service Dept closed today so it will be later this week before I find out what’s wrong. I will update later.
7/6/18, 11:48 AM
#10
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The Mustang is home and all is good. Problem was a powertrain control module relay part # L 1 8T2Z*14N089*D relay. Don’t know why it failed. Any suggestions.
7/6/18, 02:48 PM
#11
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3/1/20, 09:18 AM
#12
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same thing happening to me
what was the outcome at the dealer?
The Mustang finally got to the point where the start button would not engage the starter. I tried everything I could think of ie tested the battery, different key fob all combinations of push clutch, push brake etc. finally gave up and had it towed to the dealer late yesterday. Service Dept closed today so it will be later this week before I find out what’s wrong. I will update later.
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Shoshone Rothman
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3/2/17 06:52 AM