4WD Light switch ? - JeepForum.com
  • 1 Post By timatoe
  • 1 Post By Chrisnvegas
LinkBack Thread Tools
post #1 of 5 Old 07-07-2020, 06:46 PM Thread Starter
Registered User
1992 YJ Wrangler 
Join Date: Nov 2004
Posts: 130
4WD Light switch ?

After putting the wiring back together on our 92 Wrangler, I have found the dash light the should only come on when I have it shifted into 4WD is one most the time but flickers off and on. I checked the electrical manual and it says there is a switch " To the left of the battery on the dash panel ". That's a bit odd. The battery is no where near the dash, really.

Anyone know where this switch is, so I can check it ? I would like to figure out the connection from the transfer case to this switch to turn on the light on the dash. I know I'm not in 4WD. I did have to change the vacuum lines back to the gearbox as well as fix wires. Maybe something is not quite sealing up on those lines.

JohnW63 is offline  
Sponsored Links
post #2 of 5 Old 07-07-2020, 08:51 PM
Registered User
timatoe's Avatar
1990 YJ Wrangler 
Join Date: Aug 2006
Location: Grass Valley
Posts: 17,784
There's an explanation of the vacuum system in the FAQ's. I don't know when the switch got moved to the CAD housing on the front axle but I think it was after '91. The older models like my '90 there was a little blue canister on the firewall next to the battery. That canister was fed by vacuum from the transfer case; when you switched to 4WD vacuum is applied to the canister it created a ground path for the circuit and the light came on. If yours is in the CAD housing it's doing similar.

You can search for a thread from Anticaman on the TJ/XJ transfer case switch that gets rid of the vacuum but that also entails disabling the CAD by either locking the shafts together or replacing them with a one piece shaft from a TJ or XJ.
bruinjeeper likes this.

Originally Posted by George Orwell
We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm.
timatoe is offline  
post #3 of 5 Old 07-08-2020, 06:36 AM
Web Wheeler
Chrisnvegas's Avatar
1992 YJ Wrangler 
Join Date: Dec 2012
Location: Nevada Territory
Posts: 9,173
He's right. The switch is on the CAD. It's the only wire going to it. The wire is ground based. Meaning, the switch is a ground that complete the circuit.
bruinjeeper likes this.

"Alferd Packer: “Stand up, you voracious, man-eating son of a *****, stand up! There was seven democrats in Hinsdale County and you up and ate five of them."
Chrisnvegas is offline  
post #4 of 5 Old 07-08-2020, 08:35 PM Thread Starter
Registered User
1992 YJ Wrangler 
Join Date: Nov 2004
Posts: 130
Got it figured out.

I recall not being able to push the connector back together enough to hide the red rubber seal. So, I got some silicone lube, since it won't mess up the rubber like regular grease will, and it slid all the way on. No more flickering.

Which also showed the light was working opposite of how it should. I went back under and flipped to two hose fitting on the vacuum actuator and that fixed it. The shape and curve of vacuum lines I had to find on eBay made it fit a lot smoother the other way.
JohnW63 is offline  
post #5 of 5 Old 07-09-2020, 04:24 AM
Web Wheeler
fishadventure's Avatar
1989 YJ Wrangler 
Join Date: Jul 2013
Location: Morrisville
Posts: 7,813
You did well!

[size=“3”]Shackles & D-rings are different things.
Cranking IS turning over
fishadventure is online now  

Quick Reply

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome