I apologize for the long post, but I wanted to explain the steps I took so far.

So I recently did some work inside the truck. New basic head unit and speakers. Drove for a few days with no problems. Also took the dash bezel off to repair a broken fuel tank selector switch. The following day, battery was dead. Charged the battery, as I thought maybe I had left the dome light on. Next morning, dead again.

Tonight, I disconnected the positive battery lead and connected a circuit tester light between the post and the terminal (after pulling the radio fuse and making sure all lights/etc were off). The tester glowed with a pulse, which tells me something is obviously using power, thus draining the battery overnight. I pulled fuses one by one...everything but the flasher for the turn signal, which seems to not want to come out (dark and wet outside, so I didn't want to break something...it was hard to see what I was doing). I then began pulling fuses/relays from the power dist box under the hood. The tester light finally went out after pulling #15, which I believed to be turn signals and heater controls.

Here's my question: Can a bad flasher relay cause this, or do you think there is a loose/pinched wire somewhere? It seemed to start shortly after working around the dash area. The former owner also had some volunteer fireman lights installed at one time, so there are some wires hanging down under the dash. Any easy way to pinpoint the problem?

 

Well, here's an update. Battery was dead again this morning. Pulled battery pos terminal and hooked up light tester. Bright light, with no flashing. Pulled the fuses and relays one by one. No change. Unplugged alternator at voltage regulator and tester light goes off immediately!

I'm guessing either the voltage regulator is bad, or there's a short somewhere in the harness. I've already removed the alternator and pulled the vr and brush kit. Was hoping to pick up a new vr with brush kit, but parts stores have to order it. Besides...it's almost as much as a new as alternator. So...I think I'll just get a new alternator tomorrow. Even if it doesn't fix the problem, the alternator looks about due for replacement, anyway.

 

Sounds like pretty good troubleshooting to me.

 

Not good enough, apparently, LOL!

I put a new voltage regulator on it today (complete, with new brush set included). Fixed the battery drain issue. Light tester doesn't show a current draw with alternator plugged in. Seems like that was the problem. However, now the alternator doesn't seem to be charging. Guess I'll pull it back off and take to the parts store tomorrow to see how much (if any) current it's putting out. It had no problem charging before the new vr, so I'm thinking maybe I got a bad one.

What are the chances of getting a bad one? In my experience, pretty good. I bet 25% of the electronic/ignition/charging parts I get from parts stores are bad out of the box. I've had similar issues with dealer parts and new vs reconditioned parts. Bad batteries, starters, alternators, fuel pumps, solenoids, coils...I've had bad ones at some point.

What do you think? I'm pretty sure I put everything back correctly. I double, triple checked all connections.

 

When most of the parts are outsourced to China, Mexico, Canada even, it's hard to get consistency in quality. I remember one time going thru 3 starters before I got one that actually started the truck I was working on.

3 fuel pumps in the same day before I got one that did what it's supposed to do.

The parts manager at the Ford dealer I worked at use to give me crap about returning a part because (It was new and no way it could be bad) right up to the point where I installed one of his obviously GOOD parts on his own truck and it didn't work.

He didn't question me after that.

 

Gotcha good! Yep, most of it is Chinese junk. They are communist, and really don't have any incentive to produce a good product. I know it's a crap shoot every time I leave the store.

 

I took the alternator in today and sure enough, it's not putting out enough. Evidently, the voltage regulator I got was bad. Instead of exchanging it for a good one, I got a new alternator. The bearings in the old one were pretty noisy.

Put it on today and appears to be good to go.

 

Make sure you do not have a constant 12v draw too.

 

Yep. Hooked up the test light. No draw.