All gauges on dash suddenly stopped working

Chances are this is indeed a simple repair, but the proper way a conscientious mechanic would solve it would be to replace the instrument cluster to insure the quality of the repair. There's a lot of things we can fix inexpensively on our own vehicles, but then we have only ourselves to blame if the repair goes sour days or weeks later. Customers are not so understanding, so we pursue the more expensive repair that is less likely to cause a repeat failure.

In this case, a common source of failure is broken solder connections on the connector terminals for the instrument cluster. I've repaired these in the past, but I can't remember the exact procedure to describe it properly. Once the cluster is removed, you'll see a black rectangular plug in the center of the back. There might be a plastic cover that has to be removed first, and you might have to unbolt the circuit board and flip it over to see the connections.

I couldn't find a decent photo of a broken solder connection, but you can find a lot of information by searching for "cold solder joint" or "broken solder connection". When you look at the back side of the circuit board, you'll see two rows of terminals sticking up only about 1/16". Most will be shiny silver, but look for one or two that have a small black ring around the terminal. That's a sign of a solder joint that has deteriorated. When they are resoldered, there is very little chance the problem will occur again. These occur from automated soldering on an assembly line. That leaves lots of voids, then normal vibration eventually breaks the bond.

You'll need a small pencil-type soldering iron and rosin-core solder made for electrical work. If you don't feel comfortable doing this, or if you have to buy all the needed items, it might be a better value to look for a local tv repair shop and have them touch up the connections. I did this for 40 years as these occur in tvs all the time. The repairman will spot the bad connections right away, and resoldering them should take just a couple of minutes.

TV repair shops can be rather hard to find today. If there are none near you, look for a community college near you with an Electronics program. Any instructor there, and many of the students, can resolder the connections, and they will often do that for you for free for the good will of the community members.

That's not the solution. This did apply to '92 Caravans that had some relays, such as for the power door locks, that developed voltage spikes that caused the Body Computer to lock up. You could reset them by disconnecting the negative battery cable for a few seconds, but the problem would occur again, usually within 5,000 miles. Chrysler had a two-prong approach for that repair. They got replacement relays from their supplier with spike suppression built in, and they added circuitry to the Body Computers to make them immune to those voltage spikes. The new relays eliminated the voltage spikes, and the new computers wouldn't be affected if a spike were to occur.