Need some diagnostic help (or confirmation at-least) ...

So I'm driving down the road the other day, and my battery light comes on for about a minute then turns off (first time this has happened). Truck performance was unaffected. No CEL or other light was set, but I quickly checked my codes and found a P0611 (Fuel Injector Control Module Performance). I've since cleared the code, but it comes back.

At the time, I had my Edge Insight CS set to display EOT, ECT, & EGTE. Now, I'm displaying Batt Voltage & FICM Voltage instead.


What I've noticed via my Insight (Cold Start):

• Key On Ignition Off ... Batt Voltage = 11.0-11.2V / FICM = 48.5V
• Cranking ... Batt Voltage = 9.3-11.4V / FICM = 48.0-48.5V
• Running Immediately after Cranking ... Batt Voltage = rising to 14V after GP's turn off / FICM = falling to 35V, then rising back to 48V

My batteries are Motorcraft BXT65's (850CCA) ... they've been in service since 7/2009. My alternator & FICM are original; never touched. My passenger side battery has always had some electrolyte leakage on the top of the battery; not enough to rot the insulation wrap, but enough to look nasty & cook the various insects that happen to come in contact with it.

I'd say 1) my FICM is toast ... or at-least in the toaster (I already have a replacement PCB for my FICM on the way), and 2) I need to replace my batteries. My wonder is, do I need to look at my alternator? The most extra power I use is for a small self-enclosed subwoofer that I've tucked away inside my center console .. nothing else outside of stock.

Here's a vid of my start-up Insight readings:

 

Yep, ficm is toast. Remove the batteries and have them load tested individually. Might just be a battery problem but clean connections as well. After correcting those, retest. Ficm modules usually die from bad batteries or failing alternator.

 

X3 on the toasty FICM, the alternator is fine or it wouldn't get the batteries up to 14+ volts. The battery volts dropping under 10 while cranking shows that one or both of the batteries are about done. Just make sure you replace the batteries in pairs.

 

X4

Have batteries load tested isolated from each other.. just drive to parts store, bring 8mm socket/wrench. Remove ground from both batteries in lot, have them load test each battery. Reconnect and you are done.

It's worth replacing both batteries, THEN send the ficm to ed for repair. I also got the atlas40 ficm tune

 

Sounds like Everyones on track with bad Batterys


But I don't Agree the Alternator Looks OK But might be the Root cause batterys died (Of coarse 4 years on a Battery is about Max anymore after the originals died)

I'm saying the Underpowered Alternator caused the Batterys to get Overworked and Killed them Too

These OEM Alts the 110amp are underpowered Plus the 110amp is MAX Output at High RPM

So @ Idle OEM Alt only kicks out around 80-85amps


Guess Im getting at the Batterys would Last longer with a High Output alt
I guess in theory they should last longer

 

The culprit .....




New FICM Power Control Board, two new batteries, & a new alternator "just in case" and I'm good-to-go. That FICM connector nearest the firewall was a though!!

 

Yeah that furthest back connector is fun. Glad to hear you got it fixed.

 

I feel your pain on that back FICM connector, it's unbelievable how touh that is to get off!