MG Car Repair: 78 MG Midge- horn and wiper stalk

Question
hi- i just acquired my dads MG Midget- 1978- i need to get it inspected and noticed the horn doesn't work and the wiper stalk seems frozen/locked and wont turn on the wipers.. he just had it inspected on 7-22-15 and it appears all things passed.. what would cause these 2 issues and is there an easy fix so i can get it inspected? Thanks Tim

Answer
Hi Tim,

As I remember the horn push button is on the end of the left lever (turn signals) and the wiper switch lever is on the right side with a washer push button on it's end.

These two are different circuits so I found when diagnosing any electrical problems you should only work on one circuit at a time. The horn circuit is easy to test so start on that circuit first. You will need a 12v test light to run the tests.

The horns are powered by a purple wire on the horns from the fuse panel under the hood. Use the 12v test light to check for power on the fuse panel on both ends of the fuse that has the purple wires at one end and a large brown wire on the other end. This confirms that power it getting to the purple wire. If it does have power go to the horns and test the plain purple wires there. That proves power is reaching the horns. Now test the purple w/black tracer wire leaving the horns for power. That wire should show power too. If it does take a jumper wire and ground one end to a good ground and just touch it to the purple w/black tracer wire and it should blow the horns. This proves that power to the horns is good and the horns themselves are good.

Now, Remove the screws from the plastic shell covering the turn signal switch and the wiper switch, so you can access the switches. Take your 12v test light and probe the purple w/black tracer wire at the turn signal switch and it should show power. If it does, that means the wiring from the horns to the horn push is good. If you don't have power at that point it shows there is a disconnect between the horns and the colume switch. If there is no power check the multi plug under the colume. If you do have power at the purple w/black tracer wire at the switch then the horn push is bad.

Since the wiper switch lever is frozen the best thing you can do is to spray something like WD-40 into the switch as best you can and try wiggling the lever as you spray it. Some of the older wiper switchs could be taken apart but some are sealed and all you can do if WD-40 won't free it up is to replace it with a new switch.

You can get new switches from several on line MG parts suppliers like Engel Imports, Moss Motors and the Roadster Factory. They all have toll free phone numbers listed on their Internet web sites.

Let me know,

Howard