No headlights or dash lights

[jeepnewbe]

I am new to the site and a first time jeep owner. I have a 78 CJ7 that looks to be mostly original. The PO told the lights did work but stopped just before i brought it home. He said they flickered one morning and then went out. With the dash and headlights i think it is in the light switch. My question is terminals said i have power at different position on the switch? Can i jump out terminals to bypass the switch and check operation of lights? Any input will be great. This is a new project for me this looks to be the best site for cj info, so the will not be my only post you see from me.

 

[AussieCJ7]

There is two common spots for this

1. the headlight switch
2. the hi/low beam switch on the floor

check wiring and voltage at both you may also find moving the wiring on the floor switch they flicker on again

 

[IOPort51]

The light switch handles what may be considered a lot of current, some think, more than it can handle. Some of us have rewired the light circuts through 30 amp relays tied directly into the battery and only using the switches to fire the relay coils. It is very possible that you have cooked the power terminal on the light switch, this would cause failure to both the headlights and dash lights. The only high amperage circuit still on the inside of my firewall is the blower motor for the heater, everything else runs through relays.

 

[nctom]

I/O,
Thats a beautiful fuse/relay setup. Would you document it a little bit for us? Maybe some photos? I'd love to do something simliar.

Thanks!

 

[Shorepower]

While in college at Kent State in the late 90s, my CJ5 had a fire issue with the dimmer switch on the floor. After cutting the dimmer switch out that weekend and patching it together...all was good.

I had the same headlight/dash flickering problem that started about 8 years ago (about 3 years after the dimmer issue) while the Jeep was just sitting running at a friend's Driveway. Since then we just drove the Jeep CJ5 on the weekends during the day. We got brave over the years and ventured out in the evenings last summer...didn't have any issues all summer until we hit some railroad tracks rather fast and the Jeep got bumped around. They flickered several times and then it was fine several minutes later after sitting with the lights off. I took the switch out, it looked fine, but cleaned it with WD40 per a mechanics recommendation as that was what WD40 was originally created "per him". I did notice the terminal had been melted on the plug and replaced that terminal. It worked fine while the Jeep sat in the garage with the lights on for 60 mins and was fine after that all the rest of the summer--babied it...which was painful. It was fine this summer until I was driving around town and they started to flash. The dash switch was hot and I noticed my dimmer switch repair was coming apart. I had forgotten all about that til last weekend. I am going to test that tonight.

The discussion you all had was great and I will pass this forum onto a buddy who just got his jeep last year about this time. We have since put a new motor in it.

 

[Shorepower]

Has this happened to anyone while driving? Checked my floor fix and it is fine. May try new switch and then try relay idea.

 

[IOPort51]

I am flattered.
All the parts needed are available at


Automotive Wire Terminals - Battery Cable & Electrical Supplies

the coolest things I found were the relay blocks that connect together and the water tight heat shrink tubing.

the fuse blocks give you a fuse you don't have to stand on your head to change and a place to check voltage and amperage to the relays.

remember: there is no such thing as water proof but if you try real hard you may achieve water resistant.

the box on the bottom is a "water resistant" bus bar for the 12V from the battery and the terminal on the right is a ground from the battery, the fuse blocks are "water resistant" with a suitable fuse for the load next to a 3 amp fuse for the relay coil. All the 12V+ connections happen in the box. and the relay coils are grounded through the switch.

Now to see how it stands up to a bit of vibration.

I/O,
Thats a beautiful fuse/relay setup. Would you document it a little bit for us? Maybe some photos? I'd love to do something simliar.

Thanks!

 

[IOPort51]

There is quite a bit of amperage going through the light switch. I have melted one myself and lost the main incoming hot terminal. A replacement is not that expensive and one from a grave yard XJ will work. I think the XJ has a heavier gauge wire in the harness, you may wish to splice the Cherokee plug into your harness. A solder joint deals with amperage better than a spade connector.

Has this happened to anyone while driving? Checked my floor fix and it is fine. May try new switch and then try relay idea.