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Was driving in to work & red battery light came on along with check charging system message on center screen while on the highway. I turned around & by the time I made it home it went away. I switched it off, went inside to grab a booster pack just incase. Fired back up, went around neighborhood & message came up again. I decided to park it & took Jeep to work.
Gage showed 13.7V when this 1st happened, I had headlights, foglights, defog going as well as radio. I switched everyhing except headlights and it climbed back to 14V by the time I got home.
I just came back home in the jeep & started to diagnose the mustang.
10A fuse for the alternator sense wire looks ok.
Using multimeter, Battery showed 12.7V with car off. Fired up & it climbed to 14.4V. Negative terminal to alternator post showed 14.4 as well with it running.
Readings verified by my 3 year old assistant mechanic!
No visible corrosion at battery/alternator.
With it running, I started to load up the system by switching on every accesorie, lights, defog, etc. I then proceeded to test drive it, no battery light or message came up.
What would you recomment I look into next? Hate to get stranded somewhere...
My to do list:
Pull SJB & clean/inspect
Pull alternator to inspect/clean contacts & check with mutimeter.
Clean battery contacts & re-check all the wires for corrosion.
Test battery at autozone.
Scan with bi-directional tool & report back with any codes.
before you pull the SJB -- have you seen any signs of water intrusion?
Is the passenger floor carpet wet, or does it smell like it has been wet in the past? Are the cowl drains open or clogged?
The SJB problems happen when the cowl drains get clogged, water builds up in there, and overflows down the firewall into the SJB .... if that has not been happening, then SJB likely not the issue
check the voltage on the battery after sitting for a few hours -- should hold steady at about 12.7 volts; if not then the battery is suspect
My to do list:
Pull SJB & clean/inspect
Pull alternator to inspect/clean contacts & check with mutimeter.
Clean battery contacts & re-check all the wires for corrosion.
Test battery at autozone.
Scan with bi-directional tool & report back with any codes.
Refreshing, Somebody Willing To Go The Distance For Peace of Mind! So Few Anymore! We Look Forward To Your Findings!
Kudo's To You!
Oh and You Get a Title Upgrade Due To Your Join Date!
Gotta Have it Green Fanatic Official TMS Travel Guide
Joined: December 17, 2012
Posts: 2,566
Likes: 1,364
From: Western NC
Man, we all hate intermittent issues. Let's hope it is just the battery. 9 out of 10 times it seems to be the culprit, especially with low mileage rides.
Ref your 'to do' list, put this one at the top: Test battery at autozone
... Let's hope it is just the battery. 9 out of 10 times it seems to be the culprit, especially with low mileage rides.
...
odd thing here is that the battery is only 1.5 years old .... but if the car is not driven often, and the battery has been sitting for long periods with low state of charge, that could age the battery prematurely
I hate to say it, but I'm guilty of lurking & posting mostly when I have an issue that has me stumped.
My little helper loves wrenching & his fav tool is the ratched wrench & deep socket set!
No progress made as it was way too hot yesterday. Going to test the battery today on my way to daycare. Have not driven it since Monday, so I'll check the voltage 1st thing before firing it up.
It rained overnight so I'll also inspect for water intrusion, I do recall my seat belt being damp the other time....
Yes battery is fairly new, however like someone stated it does get drained when car sits for extended periods of time.
What replacement battery would be ideal for our cars?
So Since You Are Going to get Battery Tested This A.M. I Will Address this Often Asked Battery Question First. Since Your Battery is Only 18 Months Old it Likely Has a Warranty Still Left On It! if This is The Case and it is Bad I Would Simply Get The Hopefully free Replacement.
The Key To Longer Battery Life on These Cars seems To be the Use of a Good Battery Tender if The Car Sits For More Than 2 to 3 Weeks at a Time Without Starting.
As Far as Battery Selection if You Have No Warranty & Want To Change seems is Like Asking What is Your Favorite Color. Everybody Has a Different Take and or Preference. Some of Us Prefer To Stick With Motorcraft as it is what Came in Vehicle New! Now A Little Factoid After 35+ Years Selling Ford Parts. It's Not Always a Certain Brand Only That Has Certain Characteristics. I Use M/C Group 65 Batteries in Many of My Cars over The Years in Ford & Dodge Applications and They Hold Up Really Really Well!
Now The Batteries in the S-197-S Are Not Known To Hold Up Like That. Other Model Fords With Other Groups Also Not Group 65's Worked Better Than The S-197 Batteries But Not as Well as The 65 So Part of The Bad Rap Could Be That Certain Groups just Don't Hold Up as Well Due To Other Build Factors. It Does Not Help that The S-197 Has Parasitic Loss Issues on Top of That! Another Factoid is The Batteries That get Put in Our Cars Day One Can Be Stale From Sitting Around The Assembly Plant and Fail Early From Being on The Bottom of The Pallet at The Assembly Plant Vs The Top. So a Lot of Inconsistent Reputation Due To That Reality.
So That is More on Motorcraft Than I Have Said in a While! Oh if You Go Motorcraft Get The 36 Month Free Replacement Vs The 18! They are a Better Battery! So Others Have Other Choices & Some Say Go To Walmart & Get Cheapest Battery They Got Cause They Are Pretty Much The Same! I Just Hate Walmart on General Purposes But that is Me! Lots of Input Out There in The Forums on Batteries Aye Carumba!
There Are Glass Mat & Other Exotic Batteries Out There as Well and Some Require a SPECIAL Battery Charger and Our Cars Were Not Designed For Them So I Would Stick With Old School Lead Acid Batteries Which Have Worked Well For Years.
If You Have a Good Local Parts House You Use Why Not give Them The Local Business Vs Amazon Etc. If You Have a Good Knowledgeable Counterperson There Who You Deal With With Some Experience Ask What Battery They Have That Holds Up Well They Should Know!
Like I Said Just My Opinion as The Great Battery & Charging System Debate on S-197-s Still Goes On 20 Years Later!
While You Are Checking For Water Intrusion Might as Well Change The Cabin Filter as The Cowl Needs To Come Off Anyway! My 34K Mile 07 Gt-500 Did Not Get a New Cabin Filter FOREVER & Thankfully When I Changed it Although Due, it Did not Look Like a Mouse Had Been Living in It Like You Will See on You Tube Vids.
Oh And Automated Car Washes Can Sometimes Really Pound The Water into The Cowl Area if You Use Them as an FYI To All! More So Than Rain Many Times! My 07 Has Only Been Hand Washed and Driven in the Rain Maybe a Handful of Times at Best When Caught in It! So I Know My SJB is Dry! I really Believe If Any New To Them S-197 Owners Have Not Inspected The Water Intrusion Issue To Do So Just Because it Could Save a Lot of Grief Down The Road! Also Long Time Owners for Piece on Mind as Well!
Your Boy is Adorable & That is a Priceless Pic and a Great Time To Share Your Car With Him. Here are A Couple of Pics of My Monkeys Late 90's and The Pose in The Back of My Truck was for The MOPAR MUSCLE Parts I Had Just Scored out of Town Including a Fresh Built 440 Engine From an Abandoned Car Project. It Went into The 63 Polara in Other Pic. If You Have Been Lurking You May Know My Helper Andrew Passed Away in 2010 From Leukemia. Sarah is Now 32. Enjoy Every Minute With Your Son! Time Flies Too Fast With Your Kids!
.... What replacement battery would be ideal for our cars?
Personally I don't think they really need anything special; my philosophy is that I can't really tell the difference between a basic Walmart battery and a "better" battery, so why pay more? I buy the right size battery from Walmart and it doesn't bother me too much if I need to replace it in 4 years.
Some people swear by the Motorcraft batteries; some like some of the other fancy ones .... not sure there is any real "ideal"
Another Variable is Weather Conditions. Extreme Cold Vs Extreme Heat Could Make or Break Different Makes of Batteries and Also a Factor For Any Battery.
While We Are Diving in on Batteries It's Also Not Just Important To Keep Terminals Clean But Entire Surface as a Film Can Develop on Top and Cause a Discharge. Old School Remedy was Baking Soda & A Good Hose Down Being Careful Not To Leave any Residue Anywhere By Flushing Well With Water. Don't Need a Bad Acid Trip Man!
Ideally Removing Battery For a Swab is The Best Way To Go. In One of My Dinosaurs I Don't Have To Be So Mindful But The Shelby is a Surgical Operation!
Prior To Working at Ford I Was a SEARS Diehard Battery Man! They Worked Pretty Darn Good! We Have Not Had a Sears Here in Town For Some Time Now! The automotive Section was The last To Go! Got Some Tires There Too!
Good info on batteries, I've been through several on this car & yes no real difference between them that I could see, was just curious if there is some magical brand out there.
So sorry to hear about your little one, I know what you mean about life is too short. My dad passed away back in 2017 from melanoma, he always liked the stang. I think its why I kept it & keep tinkering with it. Sears was his favorite store ever!
So update on to do list:
Car sat for nearly 2 days, battery voltage before starting 12.4. Fired up and went to day care to get my helper. On the way stopped at autozone but their tester is broken. I'll have to take the scenic route tomorrow to get it checked out, and I assume they can test the alternator too?(would I need to remove it?)
After getting home battery was 12.8 after shutdown.
No damp carpet or insulation in firewall that I could feel. I do not use carwashes but drive it in rain if I have too. Actually I drove it through 2 winters back in 2013 & 14.
After supercharging it became a pleasure car ( did all the work my self).
Below you will find screenshots of the bi-directional scan. All of these codes are fresh as I've cleared DTCs last week when figuring out fuel pump & radiator fan issue (melted fuse on fuel pump & ****ty factory connector on the fan)
While a PIA I Would Look At All The Connections on The SJB. It's Just Been a Gremlin on So Many Electrical Issues in The Forums and if You Watched That Lincoln Video You Can See How Just One Cruddy Connection Can Cause an Elusive Issue. The Vid Really Opened My Eyes as How Important When Working With These Tiny Wires You Really Need To Be Gentle With The Connectors and Make Sure They are Very Clean. At They Very Least Pulling The Side Panel and Taking a Peak is easy Enough!
My Older Cars are Much More Forgiving But Now The Age on Them Makes Everything Brittle. Currently My Oldest Car is a 64 Which is Just A Bit Younger Then Me! Of Course it Does Not Have a Tenth of The Wiring Your Car Does. And Consider This a 2024 Probably Has Twice The Wiring Your Car Does. I Do Recall The 2024 Has 24 So Called Electrical Modules in it or Was it 32 ! Ouch!
On Alternators I Know Back in The Day The Parts Houses Wanted Them Off The Car. These Days I Don't Know. Just takes a Call.
Sorry About Your Dad. I Lost Mine in My 2003 Shortly Before I Joined TMS in 2004. I was 41 He Was 85 I was a Surprise Baby!
Battery tested as good by Autozone. Alternator I will have to remove for test as their advanced tester is broken. Not sure if this hand held paas is all that mineaningfull...
I'm going to try and get more items checked off the to do list this weekend.
SUPERCHARGED RED ROCKET ------------------Master-Moderator
Joined: May 11, 2006
Posts: 10,648
Likes: 2,516
From: Carnegie, PA
Lemod! You can also take in your alternator to any Advance Auto location and they will test your alternator at no cost... Anyway, just another option you may want to consider...
