XJ6 & XJ12 Series I, II & III 1968-1992

XJ12 Series II Ignition Switch Rebuild

Old 09-04-2011, 10:36 PM
Doc Hawk's Avatar
Junior Member
Thread Starter
Join Date: Sep 2011
Location: San Diego
Posts: 27
Likes: 0
Received 4 Likes on 3 Posts
Default XJ12 Series II Ignition Switch Rebuild

I began tinkering with my wiring today. I will eventually be rewiring most of the car to get rid of the bulb fuses and funky wiring looms. I rebuilt the ignition switch and figured I'd post a writeup just in case anyone needs it:

- Disconnect battery (lots of live wires back here)

- Remove bolt holding the ignition switch assembly to the steering column. Bolt is located in the rear of the switch assembly, near the column.

- Put a large pan or other catchment underneath your work area so that you don't lose any tiny pieces.

- Use needle nose pliers to gently pull the three locking tabs clear of the circular plastic power distribution block/back cover.

- Gently pull off the rear cover, while attempting to keep the rotating mechanism beneath it within the switch. Turn the switch upside-down so that you're pulling the back straight up. There are sprung mechanisms in here so open with cupped hands and patience.

- Once the back cover is off, remove the assembly from the car and find a clean work area.

- Remove the rotating switch assembly (little circle). A round spring and a ball bearing should be in there as well - set them aside.

- Wipe away any excess grease

- Burnish all contacts with fine sandpaper or a burnishing tool. Check all solder joints for fatigue and resolder as necessary. Inspect spring tension and ensure that all springs are maintaining contact (ball bearing, switch contact arm).

- Reapply a sparing amount of dielectric grease.

- Apply lube to lock tumbler and steering lock shaft


This can be tricky to get everything lined back up the way it is supposed to be.

- Assemble the rotating mechanism as shown below. The little contact lever should be pointing up, and the round spring should have a little tension on it in the position shown. Note which spring arms are facing down/up.

- Align the switch as shown below. Put the keys in the ignition to assist with manipulating the tumbler. Note the position of the ball bearing.

- Holding the main assembly facing upright, flip the rotating mechanism and drop it back into the assembly. The little spring should seat right on top of the ball bearing. Bring it together once for a test fit, wiggle the key gently back and forth 10 degrees or so, return it to this position and then take the top back off to check your work. If the ball bearing has been displaced, you are not getting it with the spring and you need to realign until you can get the ball bearing captured by the spring.

- Maintaining pressure on the assembly to keep everything in place, move the switch back to the car and put the rear cover back on. The wires should drape downward as you hold the switch in its installed position.

- Use the pliers again to gently but firmly pry the locking tabs back into position. Do not overtighten or you may deform the assembly. Use one tab as leverage while you push on another, as shown below.

That's about it! You should now have a functioning ignition switch that is as smooth (or better!) than the day it left the factory.
The following 2 users liked this post by Doc Hawk:
Doug (05-15-2019), Grant Francis (05-15-2019)
Old 05-15-2019, 04:28 PM
Senior Member
Join Date: Aug 2017
Location: Cincinnati Ohio
Posts: 414
Likes: 0
Received 226 Likes on 114 Posts

Today I finally got around to rebuilding my ignition switch and wanted to pass along a couple tips I learned.

The little set screw that holds the switch in the lock part is easily visable when you take the cover off. The problem is that it is very close to the console so my little cheap jewlers screwdriver was too long. The good news is that the head of the screw was big enough to grip with my needlenosed vice grips and it came right out. Separate the multi-pin conector and the switcht is out.

First step after you get it out is to use a sharpie pen to mark the metal base and the plastic top so you get it back together the same way.

Several people had problems getting the spring and ball bearing back together. The good news is if you are careful you don't even have to disturb that part. Set the switch down on the bench metal side down and hold it there. Use a knife to carefully bend the three little tabs out (be gentle they bend very easily). Holding down the base you can lift the plastic lid with the wires off with the base left undisturbed.

The plastic part with the little copper buttons was covered in old grease full of copper dust. That is probably part of the bad connection that was causing high resistance. So I used spray electrical contact cleaner and that cleaned it right up. A little sand paper and a thin coat of dielectric grease and that part was done.

Carefully holding the base together, clean the rotating copper part with the dimples. If your careful, the base with the spring, ball bearing etc stays together eliminating that whole can of worms.

Checking the marks you made, put the top back on and bend the tabs back tight and you got it. You can use a multimeter and the S57 wiring diagram and check to make sure it is working properly. Mine read 62 ohms before cleaning and .04 ohms after. The spring in the base is what makes the key spring back when you release the starter. You can use a screwdriver in the notch in the base of the switch to check the resistance for the three key positions.

Next, clean the multi-pin terminals. I read a trick for cleaning the female terminals of a multi-pin connector. Get a cotter key that fits loosely in the terminal. Cut off the longer leg of the cotter key so they are both the same length; cut a piece of sandpaper to 1/2" by 1". Slide it in between the cotter key legs and twirl it around until you have a little sandpaper cylinder the same size as the female terminal. You can then twist and push it into the terminal and when you twist it out the terminal is all shiny down in there.

The whole procedure of refurbishing the ignition switch took maybe 15 minutes after I got it out of the car. A lot easier than I imagined. I hope these tips help.

The following 3 users liked this post by Yellow series3:
Grant Francis (05-15-2019), LT1 jaguar (05-16-2019), yachtmanbuttson (05-16-2019)
Old 05-15-2019, 07:07 PM
Join Date: Feb 2010
Location: Adelaide Stralia
Posts: 19,686
Received 5,845 Likes on 4,187 Posts


I advise placing the thing in a freezer bag, so when you seperate the 2 sections, that small spring and pawl will stay IN the bag, not on the shed floor, lost forever.

First one is the scariest.
The following 3 users liked this post by Grant Francis:
Daf11e (05-16-2019), Doug (05-15-2019), yachtmanbuttson (05-16-2019)
Related Topics
Thread Starter
Last Post
XJ XJ8 / XJR ( X308 )
04-04-2019 02:38 PM
MKI / MKII S type 240 340 & Daimler
09-09-2015 11:28 AM
X-Type ( X400 )
09-08-2015 06:25 PM
F-Type ( X152 )
09-05-2015 09:10 AM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Thread Tools
Search this Thread
Quick Reply: XJ12 Series II Ignition Switch Rebuild

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: