For the last 6 weeks or so, I've had a weird issue on HER Excursion, where the battery light will blink occasionally. That is to say, it might flash off and on for 1 or 2 seconds, and then do it a few more times or not at all. It seems to be random, but last night I was able to see a small pattern in that when I accelerated hard, it seemed to flash more often during the acceleration. But again, sometimes we can drive the vehicle and it won't come on at all.

My batteries are new (6 months), plus the alternator and serpentine belt are new (9 months).

Any ideas?

 

So HER batteries are not new? Or when you say "MY" batteries, do you mean the vehicle with the issue has new batteries?

I have experienced this before. Same thing exactly. Flickering battery light, more so during acceleration. I even had a really hard shift once during heavy acceleration and the OD off light started to blink.

I believe it was an issue with tuning, but that is when I had superchips on my truck. I highly doubt that the DP you have on there has a hand in this at all.

I did end up replacing my alternator and batteries because I fried my pcm around that same point in time (my fault), and left my batteries on empty for a week and a half until I replaced it (fried the cathodes). Then my alternator got toasted trying to keep the fried batteries charged.

Anyways, you aren't the first to have this issue, and although I cannot say for sure that it is tuning or battery/alternator issue, at least you have a start.

Hopefully this helps

 

When mine started doing that it just got where the light would stay on longer and longer. Finally, the alternator died.

If you put a voltmeter on it, it will probably show normal 14.4 volts when running, but if you can measure it when the light is on you will see that its not.

One simple test that might work for you is to check the temp of the alternator in the morning before you start the truck. Just put your hand on the engine block and then the alternator. They should be the same temp. If the alternator is warm, its likely got bad diodes and is draining your batteries.

Get it resolved before it eats/destroys your batteries.

 

"HER" is in reference to "HERS" Excursion in my signature below, versus "HIS." But since HIS is my daily driver, I guess that was confusing. The entire discussion is in relation to that truck, which does have the DP Tuner in it. I agree it is not likely the DP Tuner, because it's been in the truck for 6 years or so, but, maybe the connection isn't tight. That thought would not have occurred to me...I guess I'll check it.

What's weird is I haven't been concerned about it that much, because it flashes once or twice a trip, and that's it. But yesterday it was more persistent. A couple seconds, then nothing for 20-30 minutes, then maybe a few seconds again. Weird.

 

Yup, saw the sig. Just was confused when you said "MY" batteries ha ha.

Anyways, I would make sure to get this taken care of soon. Like BigTexan said, you dont want to fry your batteries just because of an alternator. When my batteries ended up needed replacing, it was not a fun surprise expense.

 

On the top of the alternator there is a 2 wire connector. if that wiggles your battery light will flicker.

 

Mine did then when my alternator connector was loose as well

 

Randomly Flashing Battery Light - YouTube

 

Jim makes a great point, and a reletivly inexpensive fix. Altenator-rebuild shops carry those alt. connectors and it wouldn't break your bank to swap that old one with a new, I did, a whole 5.00 bucks.

 

another vote for checking your connections. If it has been an intermittent thing for the last 6 months, then I would assume that if your alternator was going then it would have went by now.

That being said it would make me think that there is an issue with a connection.

 

I'd have a spare alt. close by so you don't get stuck somewhere. I wouldn't get one that wasn't a ford one either. They are the only ones that last more than a year in my truck.