MG MGB and MGB GT Tech Talk
Suggestions please. I have a 1977 MGB Roadster and I am having a problem diagnosing a turn signal problem. I have continuity checked every connection on the right side of the vehicle; however I still can not get anything but the continuous dash light on that side. Left side works fine. If it is the turn indicator lever itself is there any way to be sure before I tear it out and order a new one? Am I correct in thinking this is the only alternative left to check?
One possibility: Some model years had the turn signals fed through the hazard switch - a faulty hazard switch might be your problem. If it's the same as mine ('76), you can temporarily connect the top 2 studs on the back of the switch to effectively bypass it.
Just had a look at the wiring schematic on Advance Auto Wires website.
http://www.advanceautowire.com/mgb.pdf
...have a look at page 25 for your schematic - it shows the turn signals fed through the hazard switch. It's worth a check!
Are you using a 12V test light or volt meter to check for power at the connections and along the signal path?
Did you check the bulbs and grounds on the right side?
If I have trouble with the turn signals then the usual situation is that nothing works - then I turn the hazzard flasher off and on a dozen times (vigorously). This cleans any corrosion off the switch - then it seems to work until the next winter. Might be worth a try, since it only takes a few seconds.
FYI - as a fellow '77 owner, look at page 26 or 33 of the Advance Autowire diagrams (they recently added a cover page, so we're all a page off from what we're used to...:))
All good advice here, but also check all the ground connections. VERY strange things can happen if dirty or missing. Clean up the bunch of grounds (black) mounted to a post on the right side fender in the engine bay above the distributor. Also check where a bunch of ground wires connect in a 4 or 6 way bullet connector on the right side in front of the radiator (where all the headights / turn signals / side markers meet up. I got fooled there this week.
I will say I DON'T think it's the turn signal switch. It's expensive, tough to find used, and a pain to change out.
Bob
