Alternator issue?

[SINAPU11]

I've got a question, probably a simple answer...but figured I'd check my thinking.
Im driving to Florida doing 60mph on i-95, heavy traffic all of a sudden all the lights and gauges, tach, spedo,fuel, etc started going crazy along with the bell ,warning lights all on at the same time. I thought it was going to shut down!
As I was looking for a safe place to pull over it suddenly went back to normal, this was a couple of hours ago and all is still normal.

The only symptom I've had in the past is the abs light going on for a second, randomly.

Checked the serpentine belt, tension is fine and no wear or cracks. Possible alternator issue is my initial thought.?? 2006 Seneca ZX C5500 6.6 Duramax

[JimD]

I do not know the diesel electronics but can give some thoughts about a gas engine version.

If your alternator failed, which I have had happen on my old dually, the only thing that "should" happen is that you no longer would be charging the battery. This happened to my wife while driving the dually. She basically ignored the warning gauge until the battery died.

So I would say a sudden loss of alternator would not cause these symptoms. Next thought, battery. Well, if that somehow got disconnected the alternator, in theory, would be able to keep things alive.

Electronics these days are mostly tied into the computer which can make things hard to diagnose. At the very least I would check both ends of both battery cables for solid connections.

Many years ago my son had a fairly new Duramax. We had just exited Pismo Beach sand dunes and had a somewhat rough ride out. His warning system was going crazy for some unknown reason. We thought we were screwed. Turned the engine off for a bit and restarted and everything was fine. I don't think he had any problems after that.

Maybe the cause was like in the James Bond movie Golden Eye. An electromagnetic pulse from a sub-orbital nuclear explosion.

[plumberdude]

sounds like a problem with grounding.

[Rustynuts]

An alternator going bad doesn’t always mean a no charge, they can go into an over charge state and that can do all kinda of things with electronics. I would start by checking grounds from the engine to chassis and engine to body first.

[RetiredOne]

How about a bad battery? I had a battery go bad (maybe internal short) and all the dash lights and indicators were going crazy.

[Grumpy]

Originally Posted by plumberdude

sounds like a problem with grounding.

X-2 Check the gauge cluster connection and the ground to the steering column.

[RVermont]

Do you have a scan gauge? When I first got my scan gauge it had a bad connector and when the wire moved it caused the gauges to swing wildly. I unplugged it and got a new wire from scan gauge and it hasn't happened since.

[SINAPU11]

Thanks everyone for all the great suggestions and feedback. I forgot to mention another symptom that might be related.

When i use the electronic liftgate it kills the motor, something it started doing the past couple of days ; similarly when i start the generator it kills the motor about 1/4 of the time.

Thanks again everyone

[DonaandDon]

Most newer autos/trucks had an ECU that retains codes in memory. Call a service tech and schedule a visit to have them read. Be sure to tell them not to "Flash the ECU".

[foglght]

This really sounds like wiring issues.