Hello all! So my '13 F-150 STX with the 5.0 has developed a rather perplexing problem. It started off with the low battery icon appearing on the dash, with the audible alarm. After a few minutes, the warning would go off. Had the battery and alternator tested and found no issue.

Drove it to Tennessee from Pennsylvania last weekend with no troubles. But the return trip was far more... eventful. While driving on I-40 in morning rush traffic towing a 4 horse gooseneck, the low battery icon appeared with the audible alarm. Then, the service icon appeared and the truck instantly stopped making power. The engine remained running but was unresponsive to throttle position. As I'm trying to coast to the shoulder though two other lanes of traffic, the engine resumes making power and we continue on. This happens two more times, before stopping at the nearest Autozone, where I had the battery and alternator tested again. Again, no issues found. Upon restarting the truck, the service icon did not come back on, so of course pulling the codes revealed nothing. Thankfully, the truck ran perfectly for the remaining 600 miles of the trip.

But now the problem has worsened. Now when the above mentioned indications appear, the truck quits making power, but does not resume normal operation. This forces me to stop, at which point the engine stalls. The truck will crank but not start, unless the ignition is turned off, and the key removed. Then... it starts and runs fine... but for how long...

And the newest symptom... Sometimes the truck won't start. It'll crank until it times out, but won't fire. I've found the only way to get it to start is to disconnect the three harnesses from the PCM. Once reconnected, it'll fire right up.

I'll be heading to my dealership on Monday for diagnostics, but wanted to see if anyone had any ideas as to what could be causing this problem. Mainly to see if it may be an easy fix, or if I am going to have to sell a kidney or something to pay for the repair.

Thank you for taking the time to read this, for I know it's a bit... long winded.

Phil

 

I'm guessing it's a battery if you haven't replaced it yet. Generally these days 4 years is about the most you get out of a battery, especially with newer vehicles. My 2013 Flex needed a battery last year and it only had 3 years on it. My truck will get a new battery before winter as it's starting to show the accessory cutoff warning in the display.

 

I have had my truck since 2013 and have had no battery related issues. In my experience a well maintained battery should last about 7 years. I hope you get this issue resolved quickly. Please look for my post about the master cylinder recall and get yours replaced!!

 

Have you checked your battery and ground terminations for cleanliness and proper torque? Poor terminations can produce these symptoms on an otherwise good battery and alternator.

 

A factory battery can last 7-ish years. Parts store ones last about 3-4. Factory battery also costs about double the price.

 

To the OP : Where do u live ?

I was just in AZ visiting my grandparents & the battery in his 15' Chevy gave us zero warning, drove around all day then stopped at a restaurant, upon returning it could barely click the starter solenoid. Apparently that's a very common practice in the desert heat.

On a side note I've already replaced the battery in my 13' F150 due to the fact that if u attempted to listen to the radio in Acc. mode for literally 2 minutes, the truck would advise "battery saver" & shut everything off. The new battery solved the condition, I live in NC.... Good luck