Random dim lights

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fxrtharley

fxrtharley

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Hi all
I have a 68 barracuda and have some odd things going on with the lights. The passenger headlight is dimmer than the drivers side. (Even replaced with same type bulb,new) The amber blinker is just the opposite, where the drivers side is dimmer than passenger side and the dash lights are barely visible at night turned up to the highest level.. Any suggestions? Thanks
 
Grounds, sockets, connections, bulkhead connector, etc. With all new wiring in both of my Darts, my dash lights were dim when turned up all the way. I installed Crackedbacks headlight conversion harness, that fixed the '69. Need two more of his conversions, but he seems to be having health issues. Not saying this will help you, but you have to start somewhere.
 
One headlight dim vs the other sort of rules out the bulkhead connector they are both fed from the same source.

As mentioned above I would first check for good clean sockets.

Don't use sand paper as that removes the designed in corrosion protection on the contacts.

Get some spray contact cleaner, and some tube cleaner brushes.

Rubber erasers are good too.

Then the grounds and any connection along the way.

Dim equals resistance that is heating up a connection and eventually will lead to melted plastic or fire.

As for dash lights

If you turn the switch all the way till it clicks are the lights brighter?

There is a rheostat in the headlight switch and a sweep. If either have excess corrosion on them there will be too much resistance and dim lights
 
I will add that I did replace both headlight switches, because the old ones were very scratchey or not smooth when adjusting the dash lights up and down. Dimness in my case with the dash lights could be there, or quality of the probably chinisium made switch. I even tried leds for dash lights, no change.
 
Had that problem with tail lights, the culprit was clamp on wire connectors used for trailer lights. Moisture got in and turned the copper wire brown (oxidized) like an old brown penny. Wires need to be shiny bright copper color. Otherwise you are just raising the resistance of the wire and the current just flows more to the good wires in your harness.
 
I suspect a bad ground up front by the grille and core support. Try running some temporary extra ground wires to see if that cures the problem. Get/make a set with alligator clips and make sure you have a good connection on each end.....socket to bare body ground or all the way to the negative post on the battery. Dash lights were never blinding on those dashes. I like using LED replacements that have a higher lumens spec. than stock incandescents. You can even change the color if so inclined.
 
Hello all, as far as the headlights go, I found the bulbs themselves were different and I am getting a duplicate lens so should take care of the problem.
I am still having issues with the dash lights. In my research it shows that the light switch is grounded by the dash but when I loosen the locknut and push the switch away from the dash it makes no difference. I am wondering if I added a ground to the connector on the switch itself that this might help the ground on the dash lights and increase the brightness since many times I am told it is the ground that causes these issues? thanks

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Couldn't hurt, but, I've never had a bad ground issue with a light switch.
 
The only thing the ground on the light switch does is associated with twisting the knob to turn on the dome lamp

The poor ground is AT THE CLUSTER. The cluster is poorly grounded by the mounting screws. There are actually several problems with clusters other than failed components

Remove cluster and.......

1...Add wire to a common ground point under a PC board mounting screw, and bolt that to the dash frame or column support

2...Inspect and clean the PC board harness connector pins, and then inspect them for looseness and solder and repair

3...Inspect bulb sockets, clean or replace, and bend contact fingers for more sure contact. Clean board traces where contact fingers rest. Of course inspect and clean bulbs etc

4....Gauges. Seriously consider replacing IVR with a solid state one. Gauge stud nuts get loose and studs/ pc board corrodes. Replace with real nuts, and loosen/ tighten a few times to "scrub" the board clean

5....IVR can lose contact as the contact fingers are not a good connection to board traces. Solder jumpers across.
 
More on the dash lights. They are a bit of a trick. There are two sources of power for the headlight switch One, UNfused, comes off the ammeter circuit and powers ONLY the headlights. Switch has a built in breaker

Tail, park, and dash light power comes from the tail light circuit fuse, so that circuit must be working for dash lights to work

The light switch feeds dash light power in, through, and out of the dash light control rheostat (twist the knob) and then out on TAN TO THE fuse box. This goes to the small INST fuse at one end of the box, then out to all dimmer controlled dash lights on orange wiring. If the dimmer control is damaged or dirty, you will have fluttering dash lights. Start by vigorously twist ing the knob back and forth about a dozen times.

Also check for corrosion/ looseness at the INST fuse, and loose wiring at the back of the fuse box.
 
There are so many bolts holding the dash to the body, it would almost impossible for it to be poorly grounded.
 
HEAD lights. I would consider re-doing the grounding. And replace the headlight connectors. Clean the HL terminals if you have not. Ground each headlight independently. Many years of these cars, the lamps ground is y'd into one wire, so if it comes loose, they all suffer
 
Murray said:
There are so many bolts holding the dash to the body, it would almost impossible for it to be poorly grounded.
Click to expand...
We are talking about the cluster, not the dash. The dash is the entire frame across the car, the cluster is the part that contains the instrumentation. IT is only grounded "by luck" by a few sheet metal screws against 50/60 year old rusted steel dash.
 
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