I'm returning from a hiatus about an issue with my truck. I do believe these are 2 separate issues. First is the gauges. Every time I drive in the fog or heavy rain, the gauges in the cluster intermittently fail. It usually starts with the speedo, then the tach, then the smaller gauges. When I shut off and restart, everything works again, but if it's been moist, it continues to repeat. The motor and A/T, AC. etc all work just fine with or without the issue explained. When I run the self-test, everything works out fine. Is the issue in the gauge cluster? Or is it in the PCM? or ? I checked the PCM connectors, and all look good and clean. Truck just passed CA smog check last week. I tend to think it's outside as the inside stays dry.
Secondly, the airbag system must have an intermittent loose connection somewhere. Any common areas to check? The warning chime/indicator lamp comes and goes. It can be very annoying as each time it resets and trips again.
One last thing? The parking brake indicator light failed, and I can't seem to locate the bulb socket.

Thanks for taking the time to read this. I am new to the Dodge realm. It's a beautiful, well cared for truck, and It runs perfectly otherwise.

 

It sounds like you are getting moisture in your connectors. I would just start checking to make sure all of your connectors are water proof.

 

The airbag may be a failing clockspring. That would cause an intermittent break. There are no other moving pieces in the SRS system.

Gauge thing may be moisture getting into the communications buss, however usually the odometer would say "no bus" if this were the case. Check connector C352 inside the driver fender well, directly behind the tire, under the pinch weld. Follow the 2 wire looms by the firewall next to the brake line distribution blocks.

98 cluster lamps should be some tiny bulbs. Remove the dash cover assembly, remove the cluster, put it face down, remove the circuit board. The motors stay in the housing.

These are from my 2001, but 98 will be similar.

 

There are many places to get a rebuilt gauge cluster with a trade in of your old one. I did it for my Step-Son's Buick Regal. Found a place on eBay that rebuilds them. Cost me $65 with core. You may want to try that.

 

"Connector C352": Is that the one in the little access cover flap inside of fender well liner? The access flap is missing, exposing some wire junction and connectors.. That may be the exposed area to moisture? Any airbag connections there too? Hmmm?

Also yesterday, the speedo pegged forward during an idle stop at a light. The truck started to sputter and stalled. When I restarted the engine, it ran ok. Triggered a Check Engine light. The code referred to the output speed sensor.

I will clean out those connections and report back. Thanks!

 

These trucks do not have external airbag wiring. It's all retained inside the cabin; the sensor that is usually on the bumper is actually attached to the firewall.

Not sure there's a cover, maybe there is, but C352 is directly under the trailing edge pinch weld of the wheel opening. You can't miss it. It has 30-odd wires that connect the PCM/engine harness to the CTM/dash harness and the chassis harness.

 

Are these the connections? This is on the front drivers frame rail, just under firewall

 

I didn't have time to open and clean out pins, but I sprayed electrical cleaner on these 3 connectors heavily last night, and this morning, there was no issues, no airbag warning. I think one or more of these connectors send the info to the cluster. (I have no schematics).
It was again foggy this am, and no issue. I will clean them out better and try to find the missing cover. Wish me luck, and THANKS!!!

 

That's actually not them, but those may be for 4-wheel ABS if your truck has that. Mine does not, and those connectors are not present.

Follow those ones to the right and under the fender. You'll see the 30 pin connector. I don't have a photo of it and the FSM drawing looks like a 3rd grader's.


This is as close as I have. The connector is right next to where the steel braided hose comes out from under the truck, on the outward side.

 

I finally found the culprit! It was the Output Shaft Speed Sensor all this time. After it triggered a constant code and was causing serious shifting issues, I replaced it. All my moisture and airbag/gauges/BUS issues miraculously all went away. And the truck now runs tip-top!