Jaguar Repair: Series 2 elect issues

Question
QUESTION: Hi im having issues with the dash lights the fuse keeps blowing whenever i connect the double white and red to the blue and red wire ,but it doesnt happen when i connect the single red and white also have noticed that slot 13 on the fuse box is empty is this normal ,really  running out of ideas on what is causing this cheers

ANSWER: Hi Ben,

I first need to know what Jaguar you have. A series II "E-type", a series II XJ-6 or a Mk II?

Howard

---------- FOLLOW-UP ----------

QUESTION: Sorry howard its a 1974 series 2 daimler and i dont know if this helps but the rheostat got really hot and now have this problem ,have spent the last few days tracing wires but can't find anythimg so i'm at a loss
Cheers nen

ANSWER: Hi Ben,

I don't have any experience or info on the Daimlers but I believe the 74 Daimler is close to the Jag sedans of that era. However, it has a Lucas wiring and most of the Lucas wiring were close anyway.

Dash lights should be all red or red with a white tracer. Blue wires in a Lucas wiring system are only head light wires so they should not be connected to any dash lights. However, Lucas does use a red W/blue tracer to power up the rheostat that controls the instrument lights which should be all red W/white tracer wires.

Do this, Remove the wires from the rheostat and take a 12v test light and check all of the wires at the rheostat. Most lucas systems only have two wires. A power wire from the fuse bax and a out put wire (usually red w/white tracer). The red w/white tracer wire will connect to several other red w/white tracer wires to branch out to all the dash lights.

They rheostat should not get hot with the load of the dash lights so look for the branch of the rheostat out put wire and disconnect them and if you have power to the rheostat only plug one wire at a time into the branch and watch which light is on. When you get to the branch wire that is shorted the other lights will dim when you plug it into the output branch. That wire is the fault and it either shorted or something it plugged into that circuit that is drawing a lot of current which is over heating the rheostat.

Lucas wiring is very consistant with their color codes on all British cars and the way I out lined to test is as we did in the Jag dealerships.

Let me know,

Howard

---------- FOLLOW-UP ----------

QUESTION: Thanks for your help turnrd out to be the fuse box some connections were loose causing the fuse to blow as soon as you put power into it,just a quick one the dash lights now come on with the indicator only happens when you put the lefthand side on aby ideas or should i replace the indicator stalk cheers beb

Answer
Something else is wrong about the fuse blowing as no loose power connection can blow a fuse. When You have a loose connection on a power supply that cuts down on current and the opposit is true to blow a fuse. Too much current is the only thing that can blow a fuse.

If the dash lights come on when you turn the left turn indicator on then you for sure have a wire plugged into the wrong circuit. There is no connection between the turn signals and the dash lights on any car.

Howard