Brake light and 4wd light won't come on - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 03-19-2015, 11:47 AM
Thread Starter
  #1
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
Brake light and 4wd light won't come on

I know I know it's better to be always off than always on, "I don't need the light to tell me if my park brake is up or if I'm in 4wd" but I have a little extra time on my hands and like everything to be perfect. I know both lights are working on the dash because they come on when you run the diagnostic thing. They don't come on however when I put my jeep in 4wd or use the park brake. The 4wd I suspect just needs a new switch I read about in another forum. What I can't seem to find an answer for is the park brake, I took out the console but don't see anything obvious.

__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 12:08 PM   #2
Commercial Member

5-Year WF Supporting Member
 
Big Sarge's Avatar
 
Join Date: Dec 2012
Location: Fort Drum NY
Posts: 5,792
For the parking brake look under the hood by your master cylinder. There is a sensor there and if that is not connected the light won't come on when the brake is engaged. Had both those problems when I bought mine as well. Plugged the wire in and brake light works properly. Put a new switch in the transfer case and the 4wd light also works now. As a quick test to be sure on the 4wd switch you can unplug the connector and jump the connector side with something like a paper clip. If the light comes on then it is the switch. If it does not then it is elsewhere. Very common for the switches to fail though.

__________________

CLICK THE LINK BELOW FOR MY CUSTOM POOL BALL SHIFT KNOBS

https://www.wranglerforum.com/f37/custom-camo-pool-ball-shifters-224388.html
_______
/l ,[____],
l---L -OlllllllO-
()_) ()_)--o-)_)
Big Sarge is offline   Quote
Old 03-19-2015, 02:31 PM   #3
Jeeper
 
pvansch1's Avatar
 
Join Date: Sep 2014
Location: Canton
Posts: 1,389
X2^ on the brake light - The wire for it to plug into the master cylinder is short, when you find it and where it plugs in, push hard until it clicks otherwise it will fall out again.
__________________
2002 Wrangler X
pvansch1 is online now   Quote
Sponsored Links
Advertisement
 
Old 03-19-2015, 02:42 PM
Thread Starter
  #4
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
Is this it? It's plugged in
Attached Thumbnails
Click image for larger version

Name:	ForumRunner_20150319_144046.jpg
Views:	34
Size:	73.6 KB
ID:	2010353   Click image for larger version

Name:	ForumRunner_20150319_144136.jpg
Views:	46
Size:	93.0 KB
ID:	2010369  

Click image for larger version

Name:	ForumRunner_20150319_144214.jpg
Views:	38
Size:	90.6 KB
ID:	2010385  
__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 02:52 PM
Thread Starter
  #5
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
There are 2 wires inside I pushed both as hard as I could I don't think they're switched either cause it used to work just randomly stopped working a while ago
__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 03:00 PM
Thread Starter
  #6
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
This is what it looks like by the lever
Click image for larger version

Name:	ForumRunner_20150319_150000.jpg
Views:	84
Size:	104.9 KB
ID:	2010441
__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 03:11 PM   #7
Mostly old school..!

5-Year WF Supporting Member
 
Water Dog's Avatar
 
Join Date: Mar 2011
Location: Now searching for rocks in Sumner, TX
Posts: 12,149
If you ground either one of those gray/black wires, the dash brake light should come on. If it does by grounding either wire, the issue is in the parking brake switch (that is attached to the base of the parking brake lever) or the connection to it.

If it only comes on when grounding one, but not the other, the issue is in the connector you are playing with or in the brake differential switch that it plugs into.

If neither wire grounded brings on the dash light, the issue is in the dash cluster or the wire run between there and the differential switch.
__________________
Dennis
Water Dog is offline   Quote
Old 03-19-2015, 03:19 PM   #8
Mostly old school..!

5-Year WF Supporting Member
 
Water Dog's Avatar
 
Join Date: Mar 2011
Location: Now searching for rocks in Sumner, TX
Posts: 12,149
Quote:
Originally Posted by jbotelho15 View Post
This is what it looks like by the lever
Attachment 2010441
That wire should bring on the dash light when grounded.
__________________
Dennis
Water Dog is offline   Quote
Old 03-19-2015, 03:52 PM
Thread Starter
  #9
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
Quote:
Originally Posted by Water Dog View Post
If you ground either one of those gray/black wires, the dash brake light should come on. If it does by grounding either wire, the issue is in the parking brake switch (that is attached to the base of the parking brake lever) or the connection to it.

If it only comes on when grounding one, but not the other, the issue is in the connector you are playing with or in the brake differential switch that it plugs into.

If neither wire grounded brings on the dash light, the issue is in the dash cluster or the wire run between there and the differential switch.
The wire on the lever is a black striped wire. The connector at the brake master cylinder has a white striped and black striped wire. The black striped grounded at either end does nothing but the white striped wire grounded brings the light on
__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 04:22 PM   #10
Mostly old school..!

5-Year WF Supporting Member
 
Water Dog's Avatar
 
Join Date: Mar 2011
Location: Now searching for rocks in Sumner, TX
Posts: 12,149
Quote:
Originally Posted by jbotelho15 View Post
The wire on the lever is a black striped wire. The connector at the brake master cylinder has a white striped and black striped wire. The black striped grounded at either end does nothing but the white striped wire grounded brings the light on
Did you have the connector plugged into the switch when you tried grounding the black striped wire?
__________________
Dennis
Water Dog is offline   Quote
Old 03-19-2015, 04:24 PM
Thread Starter
  #11
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
Quote:
Originally Posted by Water Dog View Post

Did you have the connector plugged into the switch when you tried grounding the black striped wire?
I didn't when grounding from the master cylinder end
__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 04:30 PM
Thread Starter
  #12
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
With the connector plugged in I grounded the switch at the lever the light came on. Does that mean my switch is bad or the connector?
__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 04:39 PM   #13
Mostly old school..!

5-Year WF Supporting Member
 
Water Dog's Avatar
 
Join Date: Mar 2011
Location: Now searching for rocks in Sumner, TX
Posts: 12,149
Quote:
Originally Posted by jbotelho15 View Post
I didn't when grounding from the master cylinder but did from the switch
The white striped wire comes from the ground side of the dash lamp and goes to the pressure differential switch (master cylinder). The pressure dif switch has a feed through built in so that the circuit continues down the black striped wire to the parking brake switch. With both switches connected, grounding (closing) either switch, or grounding that wire anywhere along it should bring the light on.

If it won't come on past the pressure dif switch, then the fault is in the connection there or the switch itself.

+..> dash light..> Pressure diff switch ...> Parking brake switch..> Ground
................................. |_...>Ground
__________________
Dennis
Water Dog is offline   Quote
Old 03-19-2015, 05:27 PM
Thread Starter
  #14
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
All fixed, here's what I did

Click image for larger version

Name:	ForumRunner_20150319_172732.jpg
Views:	69
Size:	96.2 KB
ID:	2010873

Now I just need to fix the 4wd light
__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Old 03-19-2015, 08:38 PM   #15
Mostly old school..!

5-Year WF Supporting Member
 
Water Dog's Avatar
 
Join Date: Mar 2011
Location: Now searching for rocks in Sumner, TX
Posts: 12,149
Quote:
Originally Posted by jbotelho15 View Post
All fixed, here's what I did

Attachment 2010873

Now I just need to fix the 4wd light
Perfect..! It just wanted a good ground...
__________________
Dennis
Water Dog is offline   Quote
Old 03-19-2015, 09:40 PM
Thread Starter
  #16
Jeeper
 
jbotelho15's Avatar
 
Join Date: Jul 2013
Location: Mass
Posts: 263
Quote:
Originally Posted by Water Dog View Post
Perfect..! It just wanted a good ground...
Yep, thanks for the support as well

__________________
04' Jeep Wrangler with Auto & Dana 44
jbotelho15 is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not 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 Off
Refbacks are Off






All times are GMT -5. The time now is 02:28 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, Gladiator, Mopar and Grand Cherokee are copyrighted and trademarked to FCA US LLC.
Wranglerforum.com is not in any way associated with FCA US LLC.