I have a '00 DD w/4.7L and automatic transmission (w/OD), and just over 327,000 miles.

About 10 miles in to my most recent errand, the "Check Gages" light came on. Not realizing that I should look at the actual gauges and not the idiot lights (duh!), I didn't take notice of them. In all truthfulness, I thought the "Check BRAKES" light had lit up (blame it on bad eyes). In any event, I continued my errand-running but figured I'd stop at my mechanic's shop on the return trip.

When I got there I told them the "Check Brakes" light had recently come on (is there even such a light?!). They added a bit of brake fluid, even though the level was adequate, and soon thereafter the light went out. "Problem solved," or so I thought.

I get back on the road and see the light come on again, but THIS TIME I notice it reads "gages" and not "brake." So I head over to a local parts store and the person there said to check my GAUGES. I did, and noticed that the needle for the gauge for the electrical system was pegged to the left. Ok...so this IS a problem.

Figuring that I'd take a peek under the hood when I get home, I head out.

Then, a few miles later, I notice the "Air Bag" light is now illuminated, along WITH the "Check Gages" lamp.

Worsening problem....

Further into the trip, I notice that the in-dash stereo is quickly alternating between "ON" and "OFF."

Next, I lose overdrive.

So, I get to thinking that we have an electrical issue, NOT a gauge issue. I then turn off my headlights (I always drive with them on) and the stereo. What happens? The "Air Bag" lamp goes dark. I turn on the headlamps, it comes back on.

Finally, I lose the odometer/tripmeter lamps, turn signals and, for all I know, brake and reverse lights.

Eventually, I make it home, but I am a bit rattled, and confused.

My best guess it that the alternator has failed or is in the process of failing.

Would some kind and knowledgeable soul help me either validate that guess and/or otherwise point me in the right direction?

Thank you VERY much.

 

All sorts of weird things can happen if/when the battery voltage falls. The cluster itself is a computer.

Check the battery and alternator but I wouldn't be surprised if you have a bad ground somewhere as well.

 

This situation has never happened on this truck for the last 2-plus years I've owned; just out of the blue.

Thank you, 00DakDan, for your help.

 

Installed remanufactured alternator two days ago and all is well.

Thanks again.

 

Thank you for the update.