Running errands all day (yesterday) with no issues. Until I get to the liquor store. When I came back out, and turned the ignition, everything starts going haywire. The dash lights are flashing, the radio display is flashing, all sorts of weird beeping noises, and my truck won’t start.
I tried to restart it a couple of times with the same result. So I get out, lift the hood, and try to jiggle the battery wires around to make sure they are firmly connected. They are. So I decided to try to start it just one more time before I call a tow truck.
Thank god! It started! And has been running fine ever since. Still though, I’m a little nervous I’m going to get myself stranded somewhere.
I know it’s not my battery as it’s less than a year old. So what’s the best guess? A short somewhere?
Aye; sounds like a problem with the battery wires or the terminations. Worst case you might want to replace the cables (and depending on how old the truck is, this might just be a good idea to do anyway).
check your battery cables at both ends. even if the ones clamped to the battery posts look fine, the other end might be degraded. Here I’m specifically thinking of the ground strap(s) to the body of the car and the engine.
edit to add: the reason this can cause the behavior you saw is because of the starter’s current draw. When you turn the key on (but don’t start the truck) the electronics and accessories are drawing a few amps of current or so. when you go to start, the starter solenoid connects the starter motor to the battery (+) terminal. But the starter motor is going to try to draw several hundred amps of current, and if the cables are degraded the voltage will drop to the point where the electronics can’t stay awake and the starter solenoid will disengage and engage over and over.
How old is the truck? very new vehicles can go “haywire” if some small thing is wrong because it is tripping an alarm. Did you get gas as one of your errands? make sure the cap is tight. A gas cap that isn’t tight can trip the automatic shut-off, and sometimes that lights will flash to let you know that that’s what has happened (other things will trip it too, like low oil). Jiggling the cables may have reset the trip switch, but until you tighten the cap (assuming that’s the problem) it will keep happening.
I once lost a gas cap and replaced it with a $4 generic one from Autozone, and kept having a similar problem. I spent $30 on a factory new exact part, and the problem went away.
If you did anything to the car when you were running errands, like getting the oil changed, check what you had done-- check the oil level, or whatever, and make sure there is nothing that would trip a warning on the truck.