oh curmbs! turn signals and brake lights were...

[Blackjokr]

working until today! I had two bad lightbulbs in the front side markers, the passenger side marker in the rear, the brake/tail light on the driver side.

So i bought new bulbs at pep boys. matches them and replaced them. Now the blinkers don't blink and the brake lights don't come on when you press the pedal but the tail lights are on.

Could it be possible that somehow in all of this I popped a single fuse that runs the blinkers and the brake lights?

Any other suggestions?

I did remove each new bulb one at a time and still no good.

GRR!!!!!!!!!!!!!!!!!!!!!!!!!! I wanted to take her to the car show tomorrow...dang it!

BJ

 

[Blackjokr]

ok so i did a little digging and am NOT an expert on wiring diagrams, but suspected they are on the same fuse. According to this, if I am reading it right..the wiper motor should have stopped working too which I just ran out and confirmed! and yes they all worked earlier today. So the diagram shows them on the same fuse in the fuse box, but this diagram shows only 2 fuses and I have four under my hood on the passengers side of the car inside the hood. Could I be on the wrong fuse box? is there another somewhere else? Again sorry for these silly requests, but so far this forum has helped this greenhorn fix his MG Midget and MGB. thanks in advance guys!

BJ

 

[Blackjokr]

https://www.thebriton.com/mgbwiremaster.pdf

 

[Blackjokr]

ok, so I am going to check the wires for voltage tomorrow before and after the fuse box. if the wires are hot to the fuse box I believe that it might be fuse 3 (3rd down from top) that is the culprit because of what i have been googling. However I took it off and checked the fuse and it seems unbroken. So I guess the voltmeter will tell me for sure because all of these darn things worked right before I left to buy the new bulbs and then stopped after I put the new ones in. Coincidence??? I think not! lol...

anyone that wants to chime in with some experience tips is more than welcome!

BJ

 

[DrEntropy]

Chopstick and some green ScotchBrite, make a big Q-Tip with 'em and polish the contacts and I.D. of the bulb sockets.

The brake lights shouldn't be fused. WHAT car is this, BJ?!?!

 

[Mickey Richaud]

Ditto what Doc said.

BUT - first things first: If the diagram you're looking at is the first one on the link you provided, it's the wrong diagram. Regardless, if your diagram shows only two fuses, it's wrong. Your car is a late model B, which has four fuses. Scroll down on the link to page 25 - for the '78 and later B. You'll notice the lights are on the two fuses with red wires; those two fuses are both fed by the red and green wire coming off the headlight switch. There's a link - the little black line you see on the diagram from the "top" fuse (on the diagram) to the one below it.

The wipers are fed by the next fuse down - green wires. Those are energized only when the ignition is on. The last fuse (purple wire) feeds things that can be turned on whether the ignition is on or off.

The best way to check fuses is with a volt/ohm meter, as a visual check doesn't always tell.

Whatever the case, take voltage readings at all locations once you've confirmed the condition of the fuses.

And remember the number one rule when troubleshooting British electricals: GROUND, GROUND, GROUND. Most often corrosion has been doing its thing and periodic maintenance is your friend. So is dielectric grease after you've polished up all the contacts. You can get that at most parts stores.

Let us know how you fare.

Mickey

 

[Blackjokr]

you guys rock! I remember one other thing: with everything off I shot a little wd-40 into the sockets to clean them. I let it dry for hours before putting the bulbs in. Now I did this on the side markers and they worked fine. Even the taillight lit up so I thought that wouldn't be the issue. I will clean those contacts and now i remember after my fuel pump incident with the ground I will check these.

DocE: Love the special tool!!! I'll be building my own today!!

Mickey, Thank you for pointing out the correct wiring diagram! I was on the wrong one!! Forgive my ignorance and bear with me a sec: The taillights work, but the brake lights don't. I think I am reading the diagram wrong, but it looks like the brake lights, the blinkers and the wiper motor all work off that same 3rd fuse and are fed with the green wires which I see do work when the ignition is ON. Again, forgive my ignorance. I am learning here! Thanks guys!

 

[Blackjokr]

what i meant to say was it looks like they ONLY work when the ignition is ON.

 

[Mickey Richaud]

what i meant to say was it looks like they ONLY work when the ignition is ON.

That is correct, Sir!

 

[Blackjokr]

ok cool so either i have dirty contacts, bad fuse or loose wire. I am going to buy some new fuses just in case. Wish they had something other than bus fuses! I assume someplace somewhere someone has a more modern fuse box with the plastic colored fuses somewhere?

 

[Mickey Richaud]

I assume someplace somewhere someone has a more modern fuse box with the plastic colored fuses somewhere?

Yep, but not cheap. And not really necessary unless you want to redo all the wiring as well. The originals, once cleaned up and maintained, work very well.

Here's the one many folks use:

Advance Auto Wire

 

[Blackjokr]

Ok I'll stick to original then. I prefer it usually. I am seriously liking the look of Some chromed engine parts or polished aluminum! Thank you for your help Mickey and everyone else too

 

[DrEntropy]

Use a test light and check the brakelight switch for proper operation, too.

I'm flyin' by memory only here, but the solid green wire should have power ~to~ the switch, the green with the tracer (ISTR it's a black one) should be "hot" when the pedal is depressed.

Brer Mick... since YOU went to the diagram, mebbe confirm or call me forgetful. :wink:

 

[Mickey Richaud]

Brer Mick... since YOU went to the diagram, mebbe confirm or call me forgetful. :wink:

So you're the eighth dwarf!

Getting ready to do a funeral, so I can't check now. But from memory, any circuit fed by green wires is only hot when the ignition is on. Brake lights only work with the key "on".

Check the link to the diagrams - page 25, I think.

Will be back on board later this evening.

 

[Blackjokr]

you guys are the best. I followed the wiring diagram you suggested. Found the fuse (3rd down from the top) and looked at it again. it was the thicker type, not the "string" of wire, but the actual band and it looked good..not broken and barely bent. anyway, bought some new 15A bus fuses at Pep boys, replaced that fuse and BAM! everything came to life! WOO thanks guys! I might just take her to the car show today instead of my GN!

Thanks again!

Lou