Ignition light
Discussion
The ignition light has failed on my car, I have proved it is not the lamp because if I try to replicate by putting a lamp between the blue wire on the alternator and the positive of the battery the lamp on the dashboard lights, but I am assuming the additional lamp I am using is completing the circuit because I think the connection from the alternator should give a positive out when the engine is running. I have the american build manual and that seems to point to the blue wire as the ignition light. Am I correct?
I think you have it backwards - the light bulb in the dash is hooked to a 12V source that's hot with the key in the run position. The other terminal on the bulb goes to the blue wire, which runs back to the alternator - it's an input to the alternator, supplying field current to the rotor ("exciting" the rotor). When you turn the ignition key to the run position without starting the car, the blue wire is basically grounded through the alternator/voltage regulator, which lights the dash light. If the dash light doesn't light up when you turn the key, I'd start by checking fuse #9 and relay C.
Gassing Station | Noble | Top of Page | What's New | My Stuff