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MG MGB Technical - Headlight switch - no parking lights

Hello all. I am new here on the MGB site. I have a MGB that the parking lights do not come on when the headlight switch is in the center position. Its a '76 Rubber bumper. All parking lights function when the rocker switch is in the headlight position. I also have no hazard-flasher function as a PO removed the flasher unit and cut wires. Could this be part of the circuit? Wiring diagram isn't helping here.

Would appreciate any help.
C.R. Tyrell

First - there is no connection between hazards and headlights. Totally different circuits without any bridging.

Second - side lamps. Everything points to the switch not making contact in the centre position. The headlamp circuit is pretty basic and simple. If you have side lights in the headlamp position, then you can rule out the side lamp fuse and wiring. How deft are you at opening up fiddly things with small springs inside..? Could you borrow a known good switch from another car and try it?

Third - Why did the PO remove the hazard flasher and what wires were cut? Sounds crazy!
Hal Adams

Thanks Hal. that is what I thought. As far as why PO took the flasher and cut wires is anyones guess. he also cut wires at the ignition switch and MAR connected them back together. fortunately the rest of the wiring seems unmolested.

As far as opening the headlamp rocker.... I can do that with good light and a magnifier. Thanks for your input I am over from the TD BBS. TD is less complicated. But wanted a car with roll up windows and a heater!
C.R. Tyrell

If the PO has hacked things around - just check that he has not changed the wiring of the lights and made it so the sides only come on with the headlights...

On the back of the headlight switch there should be four wires. One is a heavy blue wire, the other is a heavy brown wire and above this are two red/green wires - just check that he/she has not connected the blue and red wires onto the same terminal.

EDIT
I just remembered, you may not have two red/green wires, but just one. There were always two (one for side lights and the other for instrument lights, then around 75 or 76 there was a change and they joined further down the loom leaving you with just the one red/green. Principle is the same - it should be on pin 3.
Hal Adams

Thank-you. Should make it easier to track down....Thanks again!
C.R. Tyrell

Had a similar problem in my 73BGT. I removed the headlight switch and took it apart. Cleaned up the contacts with emery cloth, re-assembled and re-installed, and it worked. Before disassembling, you might even try spraying the inside of the switch with an electronic cleaner. The switch on my 73 was relatively easy to open up. Not sure if the 76 switch is that easy.

Pat
Patrick Callan

Now 50 years on - experience has taught me to carry a light switch (and one or two other nic-nacs; fuel pump etc). Perhaps most useful is the spray can of silicon - gets most electrical things going - radios, switches, mobile telephone.

FWIW
R Walker

Found the problem, now of course have others! PO put the blue and red wires on the wrong connector. Parking lights now work as they should.... then.... low and behold... tried it again and headlights come on with parking lights..... so dirty switch. Hazards now working.... wires cut to switch and blown fuse.... they now work perfect. Having a good time with the underhood fuse block.....time to invest in a good spray contact cleaner.

Thanks all for the input.
C.R. Tyrell

This thread was discussed between 09/10/2012 and 11/10/2012

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