Triumph Repair: Triumph spitfire mk1 1962, triumph spitfire mk, starter solenoid

Question
Hi

I purchased a Triumph spitfire Mk 1 1962 two weeks ago. The car appears to be original other than a bad coat of spray. The problem I have encountered is that after two weeks of trouble free driving both the front head lights no longer work (dim %26 bright). All the other electrical devises, indicators, wipers, break lights, hooter still work fine. The head lights including dim and brights worked without a problem before and no initial indication of problematic wiring or faults were spotted. I do not have a wiring diagram and honestly do not want to start stripping or disturbing electrical wiring that should be left alone. It will be appreciated if you could give me advice or assist.

Regards


Jim

Answer
Hi Jim,
It is rarely necessary to strip a harness to repair electrical problems. Most electrical problems are at the load end (item that don't work), the source (battery) or at switches, controls or fuses.

To diagnose an electrical problem you do need a few tools. First and most important is a wiring diagram and a 12v test light and for some problems you would need a volt/ohm meter. None of these tools are expensive.

If you don't have a wiring diagram you can go to my web site and copy one at,

http://mg-tri-jag.net/SpitfireMkI-IIa.jpg for the diagram and
http://mg-tri-jag.net/SpitfireMkI-IIb.jpg for the index.

Turn on the head lights and check at the load (head light bulb connectors- blue w/white or red tracer wires)for power with the test light and if you do not have power move to the next position (steering column light switch)(same colors) and if there is no power there check the power into the switch (Brown w/red tracer wire) and if still no power, move to the next position (the light switch)(power to the light switch is a plain brown wire that comes from the Voltage regulator which is powered by the plain brown wire from the starter solenoid battery position.

So you can see that the diagram is a road map and when trying to diagnose any electrical failure you should start at the load and test your way toward the battery.

Howard