Wild Gauges

Why do the needles on my dashboard gauges shoot all the way to the right and then back to normal, only sometimes, when I start my 2005 Dodge Caravan? Is there something wrong with my engine pressure?

It’s probably normal. As to the reason I can only speculate that maybe it’s like the warning lights. That is to say they all go on so as to alert the driver to any problems (burnt out bulb or malfunctioning gauge) before the start to drive.

Probably because your battery is getting weak.

Or that. Just out of curiosity (since I don’t know); why would a weak battery cause the gauges to flip up when starting?

The engine won’t cause that kind of thing to happen. There may be a processor in the dash that is causing that to happen or possibly the BCM module.

Because the voltage falls low enough during starting for the processor in the dash to crash and reset. The needles bounce as it comes out of reset.

I’ll second the weak battery. I had the same thing happen on a 2000 Ford Windstar. I had been cleaning the car and left the doors open and hence the interior lighs were on. When I went to start the engine, the engine cranked slowly and when it did start, the gauges all went to the high side. The battery was old at the time and I replaced it a few months later before cold weather.

Thanks for all responses. I’ll check the battery first. Maybe that is the problem because I’ve noticed flickering lights at times. Last year, my headlights would go off and back on by themselves. I recharged the battery and it never happened again.

ALL dashboard gauges are just ammeters, calibrated to give vario0us readings…They depend on a constant voltage to give accurate readings…Most instrument clusters have a voltage regulator of their own to insure a constant voltage…While cranking with a weak battery, voltage can drop to below what the dash regulator can adjust to…

Thanks; that’s helpful information.

There could be an intermittent problem with the voltage regulator for the gauges that Caddyman talked about and is allowing full voltage to get to the gauges briefly.

Actually, most dashboard gauges are driven by stepper motors now. Look it up.

Thank you; I shall look up stepper motors.