Single clunk sound when attempting to start. Help!

Hello all. This is my second day owning my 89 and first day of having an issue. Happy to be here and hopeful I can figure this out, I'm not giving up this early!

So, I bought the van, it seemed fine then the dreaded Christmas Dash scenario happened right as I drove off(go figure). I drove it about 100 miles today and then I stopped, loaded the van with some stuff then tried to start it again and the van had a no start(or clicking sound). I jiggled the key an tried again turning the key quickly and it started. Now I am at a friends house stranded. I go to start the van, Christmas dash illuminated, and all I get is a single clunk sound under the drivers seat. It is almost as if the starter is not getting any power and it's driving me crazy. All the fuses under the glove box are fine. The van has a secondary battery and power inverter in the back and it was all professionally done(I have the receipts). There are random wires under the dash going nowhere and an aftermarket sound system and I think an alarm. Essentially I'm dead in water and freaking out.

can anyone help me or put me in the right direction? I'm in the Sacramento area an open to havin a fellow van owner come help. Hope I figure this out and I'm not roflroflroflrofl out of luck and money.

thank you

Turns out battery was dead. 11.6 volts which I am sure doesn't give enough juice to the starter. I think the drain was mainly due to the fact that I was unaware of the button you need to press to turn the key fully off, yes I've kicked myself in the head already. But since I had over 11 volts I went ahead and checked the diagnostic codes, came up with a 12 and 51. The thing that's bugging me is that there's a bunch of aftermarket wiring installed and its a headache. So I going to jump it and take to the shop that did the work a year and half ago. But if anyone has experience with code 12 or 51, let me know. Once again, I'm happy to be here and am very grateful for all the useful information. Cheers!

sounds like a dead alternator to me or bad charge fuse or problem with wiring in the charge circuit.
NIk

Agreed. Christmas lights one the dash aren't normal and you'll get them when the alternator is dead. I've had the same thing happen when reading almost 12 volts.

I had the battery charged to 12.6, hooked it back up and she started right up with no Christmas dash. The van has a few extra inline fusebox type systems and one of them needed to be "reset". I'm taking the van to the electric shop that did the work and having them school me on what's what. So, things are looking up!

The breaker style fusebox thing I was talking about is a 50A waterproof Buss fuse with a reset switch. It is in place of the + box that comes from the alternator and it goes off after a minute or two of idling then the Christmas dash is back in full affect. This is confusing me and leaving me to think there is a short somewhere in the system, the alternator and belt look new and my battery has sufficient voltage. Any ideas?

Ive had a similar problem recently. It usually cranks just fine but sometimes i get the single clunk. I tried a few different things an it seems like a bad connection to my starter. When it happens i go jiggle the starter wires and it cranks up. Ill get around to tracking down the culprit soon. Sounds to me like your starter may not be getting juice. I also added some additional electronics into my van system but i dont think they are related. Sometimes its more than one issue at once. Maybe yours is also a battery drain and starter.