F-150 Conundrum
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F-150 Conundrum
Model: 2017 F-150 XLT 2.7 L
Location: Western AK, temps for problem arising were around 0- -10F
Vehicle Origin: Canada, currently in US
Folks I’ve got an issue that’s stumped me. I’ll start from the beginning, with what I believe are all the pertinent fact.
Few weeks ago I was driving around and hit a bump in the road, the the driver headlight flickered and went out. Thought to myself, “well, this happens”.
Driving the vehicle and we finally hit a sub-zero cold snap. The car begins to have issues starting, namely a slow crank (which is not too crazy in subzero from what I understand), and then I begin to have intermittent issues starting the vehicle on mornings and in between trip destinations.
Typically, what I see is a red “Service Charging Sytem Now” alert with the battery icon persisting even after starting the vehicle (occasionally). Also, on failed starts I am able to hear an audible, singular click. Bear in mind I’ve hooked this battery up to a tender overnight and there is definitely enough voltage, multiple load tests and eventually a professional test confirmed it.
Inevitably, after some fiddling, or even some time passing/air warming up midday, I am able to start the truck at some point in the day.
Actions I have taken:
-Tested battery
-Tested alternator
-Tested Starter
- Replaced the starter relay (This causes the truck to start back up immediately, but the next day the truck has the same problems where it doesn’t want to start, and the red battery icon/“Service Charging System Now” comes on, IDK if this was just coincidence that it worked.)
After it gets running, I think it’ll mostly start back up again after some driving around, so I think the starter test (making sure it’s drawing power) is sort of less effective as the vehicle might’ve already warmed up. Also, I have no way to test the starter cold, as I have to bring it in to town for it to be tested (single dude no other transport/limited tools).
Mechanic reports the battery is in good condition, with a strong cold crank, good alternator, and starter/alternator appropriately affected voltage (I.e., starter draws the right amount, and alternator increases the readings to 15V).
So how does the headlight figure in? Well today I got it running, for whatever reason, by leaving the key in the ON position for 10-15 seconds before finally twisting fully to crank ignition and it finally turned over (previous attempts were no crank, but still did hear the single click). Driving it around I hit a bit of a bump and the headlight goes out again, and then when I get home just for grins I tried turning it on again and it fires back up with the missing headlight operational again.
WTF is going on.
Is this an electrical gremlin? Aversion to exceptional cold? Any help is appreciated.
Yes I have checked grounding wires/battery terminals/impedance tests on fuse relay under glovebox. All are satisfactory.
Location: Western AK, temps for problem arising were around 0- -10F
Vehicle Origin: Canada, currently in US
Folks I’ve got an issue that’s stumped me. I’ll start from the beginning, with what I believe are all the pertinent fact.
Few weeks ago I was driving around and hit a bump in the road, the the driver headlight flickered and went out. Thought to myself, “well, this happens”.
Driving the vehicle and we finally hit a sub-zero cold snap. The car begins to have issues starting, namely a slow crank (which is not too crazy in subzero from what I understand), and then I begin to have intermittent issues starting the vehicle on mornings and in between trip destinations.
Typically, what I see is a red “Service Charging Sytem Now” alert with the battery icon persisting even after starting the vehicle (occasionally). Also, on failed starts I am able to hear an audible, singular click. Bear in mind I’ve hooked this battery up to a tender overnight and there is definitely enough voltage, multiple load tests and eventually a professional test confirmed it.
Inevitably, after some fiddling, or even some time passing/air warming up midday, I am able to start the truck at some point in the day.
Actions I have taken:
-Tested battery
-Tested alternator
-Tested Starter
- Replaced the starter relay (This causes the truck to start back up immediately, but the next day the truck has the same problems where it doesn’t want to start, and the red battery icon/“Service Charging System Now” comes on, IDK if this was just coincidence that it worked.)
After it gets running, I think it’ll mostly start back up again after some driving around, so I think the starter test (making sure it’s drawing power) is sort of less effective as the vehicle might’ve already warmed up. Also, I have no way to test the starter cold, as I have to bring it in to town for it to be tested (single dude no other transport/limited tools).
Mechanic reports the battery is in good condition, with a strong cold crank, good alternator, and starter/alternator appropriately affected voltage (I.e., starter draws the right amount, and alternator increases the readings to 15V).
So how does the headlight figure in? Well today I got it running, for whatever reason, by leaving the key in the ON position for 10-15 seconds before finally twisting fully to crank ignition and it finally turned over (previous attempts were no crank, but still did hear the single click). Driving it around I hit a bit of a bump and the headlight goes out again, and then when I get home just for grins I tried turning it on again and it fires back up with the missing headlight operational again.
WTF is going on.
Is this an electrical gremlin? Aversion to exceptional cold? Any help is appreciated.
Yes I have checked grounding wires/battery terminals/impedance tests on fuse relay under glovebox. All are satisfactory.
