A blinking dash?

Mountie · #1 (**permalink**) 04-10-07, 02:36 AM

A wierd occurance. Everything is fine, then, I use my highbeams & my radio shuts off for a moment, along with the dash. Then, even when I have a full tank of fuel, my mileage claims, " LOW". Then "fuel used", stays at 1.0 gallons even though it's at least 6 gallons. It's almost as if the dash info resets it'self. But then it goes back to normal....for a while.

The dash glitches, then it's fine, ..when I use something, and/or when I start the car....?... Both actually happens at different times.

Is this the computer shutting off items, to compensate for a low battery?

I have an Ultima gell battery, but maybe it's time for a new one ( after I check it)

Anyone experience a simular glitch?

**Playdrv4me** · #2 (**permalink**) 04-10-07, 08:11 PM

With a Cadillac, its anyone's guess, but I think you are on the right track. I believe the battery is starting to go and the computer is compensating but temporarily shutting off auxiliary components. At least in most cars, these are the signs of a bad battery or a failing charging system.

If it ISNT that, good luck finding out why.

1997BlackETC · #3 (**permalink**) 04-10-07, 09:29 PM

Or a bad ground somewhere.

ah2000ie · #4 (**permalink**) 04-11-07, 10:46 AM

Possibly ignition switch going out.

Mountie · #5 (**permalink**) 04-11-07, 10:57 AM

Quote:

Originally Posted by ah2000ie

Possibly ignition switch going out.

Really? ...The engine doesn't crap out...... Have you heard of this complaint before?

**Playdrv4me** · #6 (**permalink**) 04-11-07, 12:43 PM

I think the ignition switch problem affects 98-04 Sevilles and Devilles more-so than 92-97, if at all.

delzy · #7 (**permalink**) 04-11-07, 01:51 PM

I had the exact same problem. It was caused by a dirty terminal at the battery.

fiXXXer · #8 (**permalink**) 04-12-07, 09:13 AM

I, too, have had this exact problem - it happened not only when I used my high beams, but when I did anything that drew a lot of power.

You can check out the video: http://www.youtube.com/watch?v=12Hu8RwTwgo

The culprit was a dead alternator.

Mountie · #9 (**permalink**) 04-12-07, 12:37 PM

Quote:

Originally Posted by fiXXXer

I, too, have had this exact problem - it happened not only when I used my high beams, but when I did anything that drew a lot of power.

You can check out the video: http://www.youtube.com/watch?v=12Hu8RwTwgo

The culprit was a dead alternator.

I'll check the battery...... My alternator was hand rebuilt last year. The dash info shows a good charge... 13.8 to 14.2 amps.

My Ultima battery is fairly old. I'll check out this video. Thanks!

delzy · #10 (**permalink**) 04-13-07, 03:13 AM

Quote:

Originally Posted by fiXXXer

I, too, have had this exact problem - it happened not only when I used my high beams, but when I did anything that drew a lot of power.

You can check out the video: http://www.youtube.com/watch?v=12Hu8RwTwgo

The culprit was a dead alternator.

Sorry to be the one to tell you that it wasn't your alternator. It was a connection at the battery or the ground on the engine. To get that symptom, you would have to have a failing battery. The alternator's function is to charge the battery. The battery's function is to power the electrical devices. A failing battery could exhibit those symptoms, but a mostly discharged battery would show a low voltage before the power draw.

A poor connection at the battery will allow a battery to be fully charged, but will limit the current that it can provide to the vehicle. You can test for this situation by measuring the voltage drop from the terminal to the battery post while the system is under load. With a good connection, it should be almost 0 volts. With corrosion, it can approach 10 to 13 volts DC.

fiXXXer · #11 (**permalink**) 04-19-07, 09:57 AM

Quote:

Originally Posted by delzy

Sorry to be the one to tell you that it wasn't your alternator. It was a connection at the battery or the ground on the engine. To get that symptom, you would have to have a failing battery. The alternator's function is to charge the battery. The battery's function is to power the electrical devices. A failing battery could exhibit those symptoms, but a mostly discharged battery would show a low voltage before the power draw.

A poor connection at the battery will allow a battery to be fully charged, but will limit the current that it can provide to the vehicle. You can test for this situation by measuring the voltage drop from the terminal to the battery post while the system is under load. With a good connection, it should be almost 0 volts. With corrosion, it can approach 10 to 13 volts DC.

It definitely was my alternator. There were no lose connections (we checked all around) and I even had the alternator tested. As soon as I replaced the alternator, the problems went away.

A lot of people have told me that it was a lose connection, but it just didn't seem to be the case.

Mountie · #12 (**permalink**) 04-19-07, 02:27 PM

I got one of those Shumacker battery load testers. ( Yes, it's the Shumacker of drag racing fame )

I finally have time today to test my battery.

delzy · #13 (**permalink**) 04-20-07, 10:43 AM

Quote:

Originally Posted by fiXXXer

It definitely was my alternator. There were no lose connections (we checked all around) and I even had the alternator tested. As soon as I replaced the alternator, the problems went away.

A lot of people have told me that it was a lose connection, but it just didn't seem to be the case.

It's interesting that you are denying the possibility that disconnecting and reconnecting the connections at the alternator (and the battery if you followed the FSM) could have been what fixed it. Did you test the pulled alternator at the auto parts store?