Suggestions for truck electrical problem

[thatguy]

2002 Dodge Ram 5.9L Cummins - w/ Original Batteries (still showing green in the sight glass but pushing 6 yrs old)

Symptoms First noticed that the cassette adaptor for the satellite radio was reversing occasionally (which never happened before). Then one night there was a scratchy/staticy (almost sounds like the radio is eating a cassette) sound happened and the headlights/dashlights/clock dimmed briefly. The sound is loud enough to feel a vibration under your feet and hear it over the engine. The noise is happening several times a day now, but seems to happen more often as you accelerate from a stop than any other time, BUT it has done it just going down the road as well.

It is not the cassette - the noise is there even with the radio off..

Any suggestions of cause? Batteries going bad?

Thanks

Brian

I also posted this on the dieseltruckresouces.com board

 

[George2615]

Most original batteries last about the span of yours. 6 to 7 years. Stop in a local Advance Auto or Auto Zone and they will check your alternator / charging system for free. They do in my area. They will also load test your batteries which will tell you if they are bad or not. After 6-7 years I'd replace them anyway. Sometimes they don't last that long. I just had both of mine replaced (under warranty) after only 7 months. My dealer checked my charging system and batteries and determined them to be bad but couldn't give me a reason why.

 

[jinman]

I suspect you have some dirty or corroded battery terminals. It's probably the battery on the right side from the front ( looking in with the hood open). I would not only do a check of the terminals, but also crawl under the truck and look at the starter connections. You probably don't have a loose connection at the starter or you would be having starting problems. If you hear and feel a buzzing, I think you have something that is chattering. A partial ground in the solenoid circuit could cause chattering, but it also might be the relay on your dash that controls your fuel cutoff solenoid. Just make sure both batteries have clean terminals to start with. Also look for corrosion where the power is tapped off for accessories and the charging system from the battery. The terminals could be clean but the accessory power connector be corroded.

When/if you check your batteries, be sure to disconnect one battery so they are isolated.

It's hard enough to troubleshoot a problem like this when you are standing beside the truck, much less in a TBN forum. My suggestions should be considered just a guess from a guy who owns a '96 Cummins and has seen his share of electrical issues over the life of his truck. You have a lot of high current electrical circuits on that truck including intake heaters. There are just so many things. . . .

 

[thatguy]

Hmm.... the battery on the drivers side had some corrosion on the positive terminal and I cleaned it off. - IIRC it started making the noise after i did that, makes me wonder...

the terminals are tight, but ill double check them. and reclean everything..

thanks for the tips

brian

 

[RonMar]

Do you have a volt meter or amp gauge in the dashboard? If so, Can you see any movement in those needles in relation to the unusual sound? An intermittent short or open(even in a battery cell) could cause voltage surges, and resultant alternator load changes. Severe ones could cause belts to oscilate or even slip/squeek. Are all your belts in good condition and properly tensioned?

A shop that can test your alternator should also be able to load test your battery. If it is reaching a good state of charge, and passes a load test, you probably don't need to replace it, but as mentioned, you got a lot of years on that battery.

Good luck

 

[jinman]

the terminals are tight, but ill double check them. and reclean everything..

thanks for the tips

brian

Brian, here is one more tip that I'm a little hesitant to bring up, but it needs to be considered. I had a battery blow up on me in my Dodge truck. The battery on the right-front exploded like a bomb. I let the electrolyte get down below the top of the plates. When I went to start the truck, there must have been an internal spark inside the battery and the hydrogen gas exploded with a bang. I had just cleaned the terminals and was doing a test start. Luckily, I was in the driver's seat with the hood up at my house. As soon as the battery blew up, I grabbed a hose and flooded the area. There was very little acid damage, none on the paint.

This was an Interstate battery, but probably not the fault of the battery. I just was shocked at how explosive that battery was. There was not much left of it.

So be careful and check your electrolyte to make sure you have the proper level. If you suspect arcing inside the battery. Get rid of it immediately. It's an accident waiting to happen and you might not be as lucky as me. I had no symptoms and no warning. I turned the key to start the ignition and BOOM!. So be careful please.

 

[Egon]

You say you can feel a vibration on the floor of the cab at times? If so loosen off the belt tensioner and check the alternator for slack or such things.

Even better take it to a shop and have it checked out as they have proper equipment.

Do it as soon as possible as there are chances more of the electrical system may be damaged and that can lead to expensive repairs.

 

[MossRoad]

I took my family apple picking a couple years ago. We pulled into the orchard and the car started making very strange sounds. They were coming from the radio speakers, but the radio was off. When I attempted to start the car, the noises got really loud and the dash and instrument lights went nuts. I shut everything off and looked under the hood. The positive battery terminal had blown out of the battery case and was barely making contact with the guts of the battery.

I'd have your batteries and charging system checked.

 

[ByronBob]

Your check engine or any of the service lights are not on?

They can run a diagnostic check of your vehicle which will run through the computer to see if anything is malfunctioning.

A bad ground connection does do funky things. So I'm with everyone else and swap batteries and cables first and go from there.

 

[thatguy]

Update - Last night I cleaned all the battery terminal connections and reinstalled everything.. Today I drove it to AutoZone and got two new batteries. So far it has not made any more noise.. time will tell though..

Thanks for all the help

Brian