I've only read about many issues at the same time being caused by a common problem here once.
I can't point to the thread but do remember the battery was near death.

 

Thanks I'll see if I can find the post. It seems to have something to do with the central locking system. The barn door is now not opening but you can hear it trying to open after a delay when turning the key or pressing the button. All the other doors are only working manually. The other errors seem to appear when the central locking is trying to do something. I think the battery is fairly new and indeed the charge appears good - consistently 16 volts. Any experience with the central locking? - i'm inclined to disable it totally it its going to be temperamental.

 

I suggest first thing is to get the battery load tested by an automotive electrical shop.

That means some sort of specialist and not at yer LAPS. Computers are great things as

long as the battery, alternator and other bits and pieces are up to snuff, but when they

are not, it's like "what time is it when the clock strikes 13 ? It's time for a new clock !"

Some of the cranky bits are controlled by a computer, and the engine by another. Take

heed of what the truck is trying to tell you.

Uncle Bob

 

A battery with a cell or cells that are bad or going bad will cause all kinds of crazy things. You have too many crazy things happening to not have the battery load tested and tested with a hydrometer make sure that all of the cells are good. Rule out the thing they all have in common first and then move to the next part. Also, make sure battery terminals are clean and tight. Stranger things have happened and been found to be a loose battery cable.

Also, a new or even a brand new battery is no guarantee that the batery is actually good. I've had issues with new batteries that had defective plates or a short inside them.

 

I agree with everyone, The battery is going to be the first thing to look at when multiple things go all at once. After that, I'd look at the ignition tumbler. Contacts inside get wonky and cause all sorts of havoc as well. Had a friend with a Cavalier that used to have a ton of crap attached to his key ring ( you might remember back in the 90's when people had every key ring add on they could buy/attach...like it had to match their big hair..lol ) Anyway, the only way the car would run is if you slung that big old keychain over the steering column, which took the weight of the key ring off the tumbler and allowed the contacts to stay engaged....a new key cylinder and it ran like new again.

 

Hah! Battery testing. Meh!

Lump

 

TT, you see the wipers, lights and door locks all being on different circuits, if the issues are related means your looking for the common bond between them. If your sure of your battery then move to the wiring. First, clean every ground and connection or plug you can find and apply dielectric grease to keep them that way. Look for damaged wires cracked insulation, Then go to a local psychic to find the rest. I kid.
Get them all. Pay attention to the alternator too, test the voltage, if questionable take it out and have it tested. Clean and grease the big hot wire, the plug in the back and what is often missed the alt ground. It grounds through its body so the mounting bolts and where it makes contact with the accessory bracket and block can cause problems. I've seen a ground wire added to help this, I did it in my '93 on assembly.
Search this forum for "the big three upgrade" and you'll find more tips there. It is very possible you have a bad ground or corroded wire someplace that is the gremlin onboard.

 

I think the battery is fairly new and indeed the charge appears good - consistently 16 volts.

WHAT? WHAT? Sure that meter is working properly?

 

I think the battery is fairly new and indeed the charge appears good - consistently 16 volts.

WHAT? WHAT? ...

...^^^ What What he said.

Lump

 

Maintenance free battery or not. Check the water lever. 16 volts will boil the water/acid out and leave a dry cell. Alt regulator is screwing up.

 

Some great advice here, thank you. I'm going to spend Saturday following wires and seeing what they uncover or indeed what they are touching that they shouldnt be. The point about the battery was that the voltmeter on the dash consistantly shows 16 (which is apparently normal) and has done since i've owned the van. However, when the gremlins are out the voltmeter has surged to 18/19 for short periods which presume may indicated an issue with the alternator. I'll let you know what I find...

 

I would get an inexpensive electrical test meter for zero to whatever dollars and use that to test the battery/alternator etc. The thing on the dash isn't particularly calibrated. It's more of a "Looks like a problem, it's doing something it doesn't normally do". Which, from your description, it sounds like it's doing.

Based on that, I'm smelling an alternator problem.

Lump

 

The point about the battery was that the voltmeter on the dash consistantly shows 16 (which is apparently normal) and has done since i've owned the van.

Don't trust the meter on the dash, get a cheap or free digital volt meter and test. 16volts is not acceptable and indicates a problem with the charging system.

Or drive the vehicle to a LAPS or WM and have them test the battery/charging system for free.

 

Electrical tester shows 12.82 volts at the battery. I've stripped down the Dutch door and the issue seems to revolve around using the key to lock/unlock it. It seems to send the rest of the central locking system into a fenzy. Still doesn't explain why the dash gauges, heater and wipers went crazy previously. To be continued!!

 

12.8 volts is fine for engine off. A periodically bad alternator is very difficult to diagnose. Alternators are relatively cheap and I replaced mine because of some of the symptoms you describe. If you can measure the battery volts while the problem is occurring (good luck with that) then if you see much over 14.3 volts then just replace it. Auto part stores can use their tester which might tell you if you are having an issue.

 

Thanks LT, If I see over 14v when the gremlins are happening, replace battery, alternator or both?

 

I am just experiencing a very similar problem with my 2003 Astro with 44,000 miles. For a few months, every once in a while the gauges lights radio interior lights would all go wacky while driving, headlights would go off dash would go black and the tone bell would intermittently sound. This would usually last from a few seconds but no longer then 20 seconds and all would return to normal. It has not happened for the last two months. Then on Sunday my wife was on her way home. The van started normal but when she got on the road she noticed the red battery light symbol was illuminated. Also on her way home she noticed the clock was going off and on, and the fuel gauge went to empty. I had her leave it on when she got home and I looked it over. It ran fine still but the light was on, the alternator gauge was normal the clock was on and off, the fuel gauge was at empty, the interior light was on and could not be shut off. I turned the van off and it would not restart. I replaced the battery right away as it was 8 years old, but that was not the problem, but now I see the Alternator gauge is reading close to 9V so I took a chance and replaced the alternator today. Crossed my fingers and found the problem still existed. The battery light is still on, the clock and radio go on and off the gauges are all screwed up, the only way I found to get the interior light off is to lock the van. The dash lights go on and off as do the headlights. I did notice that when I pushed on the headlamp knob that the problems I first mentioned above all started happening each time I pushed the knob or wiggled the interior lamp override button. So now I wonder if the head lamp switch itself could be the trouble maker, but I have no wiring diagrams to do any real troubleshooting. Does anyone know of any common problem with these vans that would cause these crazy problems. I started checking wiring harnesses for any obvious problems and will continue exploring that, unless someone can come up with a real remedy on this. Thanks for any help. TT if you are still out there did you ever find a cure for yours?