Hi all, we have a 2001 F150 Super-Crew (5.4L, 2V, automatic transmission, 2 wheel drive) truck that has been a very good vehicle for us. We have some kind of drain on the battery and I am trying to find it. I am recharging the battery right now and when it is done I intend to get my meter out and see if i can find the source of the drain. Anyway, for some reason, in the past whenever we have disconnected the battery (either to replace it or to do some work on the truck) we can count on the truck not starting due to the PATS system. Don't know if something is wired wrong or what, but I had to have the truck towed home from Costco a couple of times, after getting a new battery installed. Also in the past, after we have disconnected the battery to work on the truck, when we re-hook the battery up, it won't start. Just cranks. Over the years I have gotten different advice on the PATS system and the blinking theft light, even looked looked online for a PDF of the PATS system that could help (never found a good one). My son usually will have to come over and spend hours trying different methods he finds online to get the truck to start. He writes down what worked but says it is never the same method when he has to do it again

In any event, every video of doing a parasitic drain test involves taking the negative battery cable off and wiring a multi-meter (set to 10 amps) between the negative battery cable and the negative battery post. My fear is that in doing so, that once I am done with the test, that I will have the same trouble with the PATS system, preventing from starting the truck. I am wondering about hooking up a BATTERY SAVER device saver while I unhook the battery to wire in the multi meter, then unhook the BATTERY SAVER device while I search the fuses for the parasitic drain. Then, after I have found the source of the drain, I can re-use the BATTERY SAVER device again while I re-hook up the battery. Do you folks know if this will keep the PATS system happy? Are these BATTERY SAVERS a good idea? They have some that use a 9 volt battery, and they have some that plug into the OBD2 port - which do you guys think is best?

My wife and I are seniors on a very limited income so taking it to a mechanic ($$$) is not an option, especially here in California. However, although I may be slow and don't have the best eyesight, I usually find and fix what needs to be fixed.

Let me say in advance that I appreciate any and all advice so pour it on!

 

Only chance would be one hooked to the obd port with a 12 volt battery supply.
One thing... If you have any after market security system or remote start devices, begin looking at them first. Remove them .
I see those cause all your complaints often in my shop. I remove them often, many people buy used vehicles and don't even know they have one.

 

The truck has the 2 key fobs that came with the truck when we bought it new (have since replaced the FOBs a couple of times over the years.) We have to start the truck within 15 to 20 seconds of hitting unlock or the PATS system will keep the truck from starting. If we don't start the truck in those 15 to 20 seconds, we have to hit unlock again on the key FOB. And when we disconnect or remove the battery, it's a nightmare to get the thing to start. Been to a few mechanics and they just scratch their heads. If I could remove the dam PATS system, I would in a heartbeat.

 

Hi all, wanted to give an update. Charged the battery again and got the truck to start. I was able to get a battery tester (the Ancel BA101) and after going through the testing sequence, it said the battery is good, but that the alternator is charging a little high?? I made sure their were no lights left on, or any other obvious current draw (radio, etc) and left the truck overnight. Came out the next day and tested the battery again. it still said the battery was still good, but that the charge level was down(around 70. I was able to start the truck, and let it run for a while to bring the charge back to 100%. Anyway, it seems that I have some kind of draw on the battery. I know I will have to get the battery load tested somewhere, but my primary concern is the parasitic draw, AND the PATS/starting nightmare that happens when the battery is unhooked. If anyone has a good PATS system troubleshooting link that would be great.

Incidentally, I do want to say thanks again to all who offered help and advice. Even if we could afford a mechanic, I am not able to drive anymore, so I couldn't get it tested. My wife and i are seniors doing our best on a VERY tight budget so i try to do/fix as much as I can to keep things going without having to spend any money. I know there are some here who probably wonder why i don't do certain things or take certain steps. Well, I am disabled and can't walk without a cane, and my vision isn't the best, so it is hard for me to work on the truck. But i do truly appreciate and and all advice given, and I apologize for my repeated questions - i'm just trying to find a way to fix things under the circumstances we are in with the tools that I have