My personal pickup. Wife called this afternoon. No start. Dead. Got home dome light came on as well as dash lights, normal. Put key in, everything goes out, dead. Boost with the work truck starts fine. Let it run, still hooked to the work truck, around 30 min. Unhook work truck, meter says charging. Turn truck off, needle on meter up and down 12 volts, the 9 volts, 12, 9, and so on. No start dead. Unhook, load test 3 volts. Hook back up, boost, start, run. Shut off dash lights on, off. radio lights on, off. power window lights on, off. Hook non running work truck up, starts runs. Leave hooked to work truck, shut off, all lights go out, everything normal. New battery everything normal. Would a bad battery cause the truck to not be able to go to sleep the right way, or do I have a bad body control module? If this new battery goes dead, I'm thinking on doing a draw test. One would think that the new battery would go through the same issue with the lights if it was a BCM.
I've had weird things happen when a battery went kaput and I didn't realize it. Really bad battery and you can't even boost it.
Even a new batt can be wonky, nowadays.
I don't know much about trucks but I've also seen weird things happening with batteries and all the electronics in vehicles nowadays. We had a Town and Country once and one day the locks started engaging and disengaging quickly without messing with them, then the dash lights went all goofy. The van continued to start and run fine but seemed possessed. New battery fixed it. If you are already running a new battery that sucks.
Might be bad connection or broken wire too
X2
My father in laws truck was a crank no start one day randomly, would crank what seemed normal just wouldn't fire off and it ended up being a battery. He had some weird issue with the clock as well that were resolved when battery was changed.
My 17 Silverado acted like that when the battery went bad
Seems fine with the new battery. I guess they have an issue with the park switch on the floor console. That was one avenue I also explored, but the switch was fine. I used to belong to an F150 forum, but if they don't know, they just make crap up, and belittle each other or me, for not knowing. I find it safer to post on here.
I've had multiple non-battery issues that initially acted like a bad battery across my trucks and equipment. A loose or corroded connection will give enough voltage to say it's good but when you try to draw a significant amount of amps through it (like starting or charging), the bad connection will cause too much resistance and create large voltage drop in the circuit. The only way to find these bad connections is trace the circuit under load which can be frustrating when in a starter circuit cause you need someone cranking while you're probing with a DVM. Same goes for bad connections with BCMs, ECMs, etc. One frustrating issue I dealt with was on my old JD 401C front end loader with 2 batteries wired in parallel for 12v to start the 4-banger diesel. These aren't big batteries, something smaller than the group 65 typically found in pickups. More like a mid-size car battery. One day, the tractor was slow to turn over and I needed a jump from my pickup to get her going. Tractor fired right up as normal with the jumper cables so I figured my tractor batteries were low or bad. I took the batts home and hooked them on the charger but each said fully charged. To be sure, I even left them on overnight on a trickle charge. After cleaning the terminals real well, I put the batts back in the JD and again got a slow crank but again the tractor fired right up with the jumper cables. Now I'm thinking the batts couldn't produce good current under load and thus were bad. Took them out to a auto parts store but there the JD batts tested good under load. So to verify the tractor batts were good or bad, I put them in my pickup (older Ford 7.3L Powerstroke) that I used to jump the tractor and boom- truck starts right up! And it seemed to crank faster with the JD batts than my pickup batts. Now I'm really confused as the tractor batteries appear good. I rule out a bad or corroded connection across the tractor because the jumper cables make the tractor crank and start quickly. So now I'm thinking there must be something causing the slow start between the batteries and where I connect the jumper cables. The problem is I'm hooking the jumper cables directly on the battery clamps. But after closer inspection, one cable clamp is cracked right by the bolt which means I'm only effectively using one battery for the slow start. Anyway, I replaced the battery cable and all is well. So yeah, "battery problems" aren't always because of the batteries.
recent experience with the work truck. The one way clutch on the pulley started going bad, caused all sorts of fun until it totally failed.
My mother's 2010 escape wouldn't start. Battery was dead. Unhooked it, and put it on charge. Battery tested bad. Replaced it, but noticed quite a spark when I hooked it back up. Put my meter on it, and waited for it to go to sleep. It had pretty good draw. I laid the meter against the windshield so I could see it. closed the doors and waited for it to go to sleep, then began pulling fuses. It turned out to be the rear wiper. She still has it, and it has started again, but this time I am suspecting the key switch, as the dash lights are staying on. It acts like the key is in the ignition
I'm not a fan of modern automobiles that the ability to draw that much of a load on a battery when it's "off". Like my yellow equipment, I kinda wish my vehicles had the battery disconnect switch to isolate the batteries when not in use. Don't get me wrong, I enjoy the creature comforts of a newer vehicle but it's getting to the point I can't troubleshoot them anymore and it's better to "trade up" then deal with the electrical gremlins as the vehicle ages.
Yeah funny how "they" want everything to be electric now, and seems nowadays no one remembers how to build a good battery.
Now I'm really confused as the tractor batteries appear good. I rule out a bad or corroded connection across the tractor because the jumper cables make the tractor crank and start quickly. So now I'm thinking there must be something causing the slow start between the batteries and where I connect the jumper cables. The problem is I'm hooking the jumper cables directly on the battery clamps. But after closer inspection, one cable clamp is cracked right by the bolt which means I'm only effectively using one battery for the slow start. Anyway, I replaced the battery cable and all is well. Yes an OHM meter test can tell you if you have a path from end to end of a cable, but only a DVOM will tell how much voltage is lost while under loaded test. After all if there is still one strand of copper from end to end, you have a peerfect Ohm test. Just wont start. Stab one end of cable with one test lead, stab the other end with other test lead while someone holds the key switch to start and if you have a reading over 0.4-0.5 volts on the cable something is wrong. Hope that helps. Simon C