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No headlights?

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William

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Apparently the headlights have gone on Dad's B. Hit the switch, the side and taillights all work, but the headlights dont. What weirds me is the fact that the little blue light on the dash comes on. I presume it would not if the fuse was bad. Am I wrong on this? (No shop manuals handy!)
-William
 
I don't know what year your B is, but this happened to me a month ago. I was using the headlights just fine, then all of a sudden only the driving lights would come on, but no headlights. I hit the high beams and they worked OK, so I suspected the switch. Removed it (71 B has one of those black rocker swithes), disassembled it, cleaned the contacts and it worked again! It took some tweaking too, didn't work right away, made about 3 attempts. That might be your problem...
driving.gif
 
The suggestion above is good...

Also, try "rocking" the high/lo beam switch back and forth with the headlights on....my Spridget has this problem at the moment. A little spritz of Radio Shack Electrical Contact Cleaner might help.

If none of this helps, look at the headlight grounds (OK...."earths"). Then, I'm afraid, it's time to bring out the dreaded wiring diagram.
 
William, What year is your Dad's "B"? I've got "B" wiring diagrams handy up 'til '72, and can possibly help by telling you which wires to jumper to check the circuitry.
I had a similar problem on my '72 Midget, that turned out to be the steering column dimmer switch, and the systems are essentially identical.
Jeff

[ 09-01-2003: Message edited by: Bugeye58 ]</p>
 
The light switch is a common failure in the "B", at least in mine. 3rd one in 22 years. The symptom is the headlights get intermittant and rocking the switch will bring them back on.
 
Car's a '71. Pretty sure the steering column switch is all right-they were replaced a year or two ago, and all other functions work (except the high beams at the moment!) have not had the chance to go out and play with the rocker switch. I'm hoping that both lights blew out at the same time!
-Wm.
 
If you look at the diagram on the web site supplied by Andy you will note that the 12 volts goes to the light switch (6) to pin 1. Pin 2 is the out put to the running lights and other lighting. Pin 3 goes to the dimmer switch (26).

So, if pin 3 of the light swotch (6) is bad, you will have all the other lighting circuits working and there will be no headlights either high or low beams. So, if there are no high or low beams, the trouble will be from and or including pin 3 of switch (6) through the common lead of the dimmer switch. If only one of the head light functions (high or low) are working, the problem is at the dimmer switch or out the wires to that function that isn't working.

If you had a bad ground, I would think one of the headlights would be doing something since they are probably grounded individually.
Bob

[ 09-01-2003: Message edited by: mrbassman ]

[ 09-01-2003: Message edited by: mrbassman ]</p>
 
Bassman, the symptoms of my dimmer switch failure on the '72 Midget were no low beams. All other funtions were normal. (The initial failure mode of the original switch was the fact that it caught fire!)I replaced two of the after market, "Made in Taiwan" switches within six months before finally adapting a genuine Lucas switch from a "B", that has performed flawlessly for three years. Imagine, hunting for a Lucas switch for reliability!
confused.gif

Jeff
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Bugeye58:
Bassman, the symptoms of my dimmer switch failure on the '72 Midget were no low beams. All other funtions were normal. (The initial failure mode of the original switch was the fact that it caught fire!)I replaced two of the after market, "Made in Taiwan" switches within six months before finally adapting a genuine Lucas switch from a "B", that has performed flawlessly for three years. Imagine, hunting for a Lucas switch for reliability!
confused.gif

Jeff<hr></blockquote>

That would be correct. If you had either high or low beams without the other, then I would say the dimmer switch or the wireing associated with it was the problem but William sounded in his first statement that he had a complete headlight failure which I would think would be the light switch but in his second statement it sounds like he has high beams and thats why I made a statement that covered both. I agree that if in fact he has high beams only, the problem would most likely be the dimmer switch.
 
Bassman, that was the way I read William's postings, as well. The initial one indicated a light switch failure, the second one a dimmer switch, or simultaneous headlamp failure. A good example of trying to troubleshoot with insufficient information!
Jeff
 
Oops, I just noticed a mistake in my statement before the last one and corrected it. In the second paragraph I said pin 1 on the light switch and it should have been pin 3. That is the pin that sends the 12 volts to the dimmer switch.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Bugeye58:
Bassman, that was the way I read William's postings, as well. The initial one indicated a light switch failure, the second one a dimmer switch, or simultaneous headlamp failure. A good example of trying to troubleshoot with insufficient information!
Jeff<hr></blockquote>

OK, gotcha.
Bob
 
Not being electrically gifter, I've found that a regular cleaning of all the connection points with spray electrical contact cleaner keeps everything working properly....bet if you pull your switches & bathe the contact points on them & in the plugs the problem will go away....
...a good way to ensure proper operation is do a section of the harness at a time....about once a quarter pick a different area (under hood/front of car, dash, trunk/rear of car) & spend a Saturday disconnecting everything in that area & bathing it...also loosen all the grounds in that area, bath them & reattach.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>What! Bathe every three months?! Sacre' Bleu. <hr></blockquote>
Yep, whether you need it or not...actually, you really only bathe a section of the car once a year using that rotation!
 
Hey, once every 15 years or so...I woke the '79 Vermillion Red up this summer & its just as good as new....doesn't even mark its territory - &, everything works!
 
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