08-22-2014, 11:32 AM
Join Date: May 2014
Originally Posted by rtoora
The first issue is with the horn.
I have just been working on the horn on my 88 (I know my user says 87, but I have since switched to an 88) and if your 87 is the same, it works by grounding between the steering shaft and a wire in the column under the steering wheel. Pop off the steering wheel center horn pad and you should see a metal piece with 3 tabs on it. When you push the horn pad it makes a tab (or all 3 tabs) contact the metal piece beneath it. This completes the ground and the horn should blow.
To test your horn, run a jumper wire from the nut holding the steering wheel on and touch the top metal piece (the one with the tabs). The horn should blow. If it don't try grounding somewhere other than the steering nut.
If it still don't work, gently remove the tabbed metal piece by pushing the plastic catches back and lifting it out. Don't lose the little white spacers! Clean all the terminals and points of contact. This tabbed piece has a contact finger that goes inside and touches on a contact ring under the steering wheel, and this ring also gets corroded, so that could be the problem. This ring has a contact on both the top and bottom sides of it. You have to pull the steering wheel to get to it.
If it still don't work, you may not have a good horn. You can test the horn easily with a 12v hot wire and a ground, just touch one wire to each horn terminal.
To test if your steering shaft isn't properly grounded, run a jumper between the steering shaft (above the rag joint) under the hood to a good ground. The rag joint between the shaft and the steering box is a possible place for a bad ground connection on the steering shaft.
My horn now works part time, problem is just a bad connection. I think its on the contact ring. I cleaned one side of it when I pulled the steering wheel off, but you can't hardly clean the upper side of it. Don't be afraid to get a puller and pull your steering wheel. Just mark its position with a punch on the shaft and the wheel before you remove it.
The second issue is with the speedometer.
The speedo is cable driven from the transfer case. See if your cable is still installed in the case. If so, remove the little retainer bolt (10mm head IIRC) pull the cable out and spin it by hand or with a cordless drill and see if the needle on the speedometer jumps.
If it don't, your cable may be broken. If it does, you may have a cable drive piece inside the case that is bad. The drive piece also comes out, it is retained by the same bolt, but they can be a bear to get out. If you get to that point and need help getting the drive out, I can tell you how to make a puller for it.
Hope some of this helps you out.
Last edited by texas 87sami; 08-22-2014 at 11:38 AM.