Well, as luck would have it...

Started up my van to do some diagnostics work this morning...

Fired up... ran fine.

Shut down.

Then when I tried to start it again... it died.

The symptoms:

Gauges go haywire, (wobbly), ABS light is dim and blinking

Strange noises being made.

Starter does the "click" and no crank.

---------------

Out comes my diagnostics tools....

Voltage... 12.0 volt with nothing on.

Cleaned terminal (at junction box, not battery).

Same thing.


--------------

Put a charger on it... and after 5 minutes at 6 or so amps (as measured)...

Lights, panel, ABS right back to normal.

Have not attempted to start it yet.

Figured I will not risk the FICM on a low voltage start.

-------------


So, off to repair shop to get Ford to pony up get another pair of Motorcraft batteries (3 year free replacement), and also get misc. work like have the alternator tested.

Shop that did my alternator / batteries is the one who put it in originally --- so let them see their own handiwork.

Get an oil change done at same time with 5w-40 dino for the summer (synthetic is slated for winter change, when it does most good).


So to all the great experts on here... bismic, cheezit, rick, d8schum, maximum4X4, tex, etc.

Thanks very much for sharing your expertise.

You sure helped me not spend a lot of money needlessly!

 

My alternator was fine but my almost 4 year old MotorCraft batteries died....$230 later and Interstates, running fine. One morning I got the slow crank, I'm like Oh noooooo, so I started checking.

 

Gear,

Be careful here, you may spend more to fix it than you paid for it

 

Well, the batteries are free under the 3 year warranty.

So if there are no other concerns...

I get off light this time.

 

How many miles do you put on your truck each year? Reason I ask, is if you're changing between dino and synthetic oil twice a year, that's a lot of mixing of different oils. Especially if you only change it twice/year, you'd be better off just sticking with synthetic year round.

 

Woa!

I am not mixing dino and synth.... I am migrating to synthetic slowly from 15w-40 that is in it now.

Gradual phased migration (because of the 1.5 gallon I can't get out).

Once it is migrated to synth 5w-40, it stays year round.


As always, thanks for commenting --- I learned a lot from your posts.

 

Are low voltage starts bad for the FCIM? The reason why i ask is because my interstate batterys are goin bad in my rig. I replaced the alt last month to lol

 

It puts more stress on the boost converter in the FICM that steps it up to 48V. To get the same amount of power at 48V with lower battery voltage, it has to handle more current on the 12V side.

 

Ok, so it aint smart to run around with bad batterys or lets say drain the batterys with the radio or lights on and then start the truck? The truck starts fine if you start it with out havin the lights on or radio on before you start it. But if you have the lights on/radio on before you start it, it seems like the batts are drainin fast

 

Sounds like you're needing new batteries then.

 

The oil system holds around 18 quarts. System capacities vary a little depending on the year model. What is left is about 1 gallon.

 

Yup.

Check the link below for alternator (field winding) wiring problem....

Always test that before you replace the alternator.

 

Legally, in my jurisdiction, I don't have a choice. The lights are "always on".

So guess what some enterprising geek did...

 

Mark,

Thanks as usual for your great advice and posts.

 

Already replaced the alt when i first bought the rig. So i think its new batts this time. BTW, i looked under the hood today and the previous owner replaced only one batt. Theirs two diff batts under my hood

And thanks cartmenea