Section : Electrical Equipment

More electrical gremlins 

Posted By : Jonathan Parsons, 06-May-2005, 06:27pm

• More electrical gremlins 

  Posted By : Jason Chinn, 17-May-2005, 07:11pm

  Electrics, my favourite, NOT. I have a similar problem with my overdrive, I suspected the switch but it looks OK and tests OK. Does your fuel gauge read OK? Instrumentation issues make me think of voltage stabiliser - talk to James Carruthers, he's got the makiings of some nice new solid state ones - much cheapness

• More electrical gremlins 

  Posted By : Colin Wake, 17-May-2005, 07:40pm

  Jonathan
  
  The Supply to the overdrive relay should be live all the time. The supply the overdrive switch should only be live with the ignition on. Also make sure you have a fuse in the relay supply wire as D-Type overdrive can burn the wiring out of they fail.
  
  The Overdrive relay is identical to the horn relay and they should be clamped back to back on the side of the battery tray.
  
  Ignition light may be wired wrong, but I suspect the diode pack in alternaor or the voltage regulator for the dynamo has failed. If the battery is charging, it may be a job for next time...... Why do today what you can put off until tomorrow, that's my motto!!! I have to say I have limped home a few times when the battery hasn't actually been charging.......
  
  I suspect someone has been fiddling, did the car originally have OD???
  
  If not, they have probably bodged in an incorrect relay.
  
  Cheers
  
  Colin
  TSSC Suffolk AO
  
  

  • More electrical gremlins 

    Posted By : Jonathan Parsons, 18-May-2005, 12:30pm

    Thanks for that. THe OD seems to be having a spell of working normally at the moment although I know that just by saying so it will probably pack in again! The switch is definitely recieving a current without the ignition being switched on so I suspect a short or a previous botched job (maybe in an attempt to overcome the current problem). I will just have to follow the wiring diagram and see where things have gone wrong.
    
    The ignition light failiure would appear to be earth related as if you touch the bulb body to earth it works. Having driven the car for the first time at night recently I now realise that the whole dash lighting is faulty as everything flickers, which can be very distracting.
    
    I will follow your advice and put an in line fuse in the OD circuit. Excuse my ignorance but where is the best place to put it? live feed into the relay?
    
    Jonathan

    • More electrical gremlins 

      Posted By : Chris Taylor, 18-May-2005, 03:04pm

      Not absolutely sure abuot the fuse, but logically putting it in the feed to the relay should provide maximum protection to as many components and wire runs as possible with one fuse.
      By the way, does anyone know WHY the feed to that relay is live all the time? Triumph had some funny ideas on fusing etc (eg Heralds had NONE!), and there are a limited number of terminals and current capacity on the ignition switch itself, but I can see no reason why you should want the relay live with the ignition off (unlike the lighting of course!)
      
      The earthing of the bulbs in your instruments explains I think why both the ignition and oil pressure warning lights don't work! I'm not sure what the original arrangement was meant to be, but an earth from the instrument case to the dashboard metal surround should cater for both warning lamps and instrument illumination.