mrclean took my guess. Have this problem with trailers and the lighting on them.

 

I'm seriously going nuts...

I can't find the source of this problem...

I appreciate the help though...

 

Everytime the lights flicker, the voltage gauge shows a slight drop (.5 volt) for each flicker, never below 14...

I don't know what else to do/...

 

Bad chassis ground? There are usually a few wires connecting the engine block to the chassis. Maybe one or more of those wires has gone bad or corroded at the connection? Just a guess...

 

I also have the same problem with my 97,dash and head lights flicker but not at idle. I can see my charging gauge flicker at the same time (discharging) I have watched the gauge during daytime driving without the headlights on and it is still flickering. All other controll functions like blower motor, turn signals, radio etc...have no effect on it. I have been watching this for about one year, It doesnt do it all the time but is getting more frequent??? 132000mi with stock alt.

 

well my shot in the dark here, i had a 70 road runner, a 74 cuda, and a 71 duster that always did this same thing, and the solution turned out to be so simple . i'm not sure how the guage in the dash is set up on a 97 p/u but on my cars the isolator where the hot lead went into the volt guage had loosened over time, and when ever i hit a bump the hot lead would ground out and "funky disco light" syndrome would occur. i also was constantly frying the fusable link too. not sure if this is related at all but if you only have short hairs left to pull (LMAO) maybe worth disconnecting the battery and havin a peek at the connections on the back of your volt guage, give em a wiggle ( after you disconnect) i bet if they move there shorting out through the dash. good luck on that.

 

I just fixed the same problem, the wire was loose behind the fuse box. I hate electrical problems!!!

 

Just as your trailer lights will flicker with an intermittant ground, your headlights are losing their ground connection. Need a service manual to check where your grounds are located. Corroded or broken ground connection.

 

Newbie dumb question!!!

Do you have an aftermarket voltage gauge wired to, or near the main battery terminals or is it something that is wired into the computer? If it is driven by the computer or other transducer and not directly wired to the batteries you may be able to use the information from the gauge to aid in diagnosing the problem.

Define the flickering as best you can and also indicate if it manifests differently under certain conditions. This information could also help in troubleshooting the problem. All sugestions mentioned before are valid rabbit holes to run down.

The trick is to use all the clues Watson, or Grasshopper!


Joe

 

I'm not an electrician but here is my thought. If the lights dim and the voltmeter drops would this not indicate additional draw? ( possible short )
If the lights dim and the voltmeter rises wouldn't this indicate a loose connection?

 

Yes Wolfman. That is what would happen.

Joe

 

I have a chaffed wire on my negative battery post. My lights are flickering and sometimes when I have the lights on at night and turn truck off everything dies. Any help ?