+ - 12V supply test
|I will be asking you to test voltages on IC pins next. You need sharply pointed test probes to do this, as you must pierce the varnish that is coating the board and components. If your test lead slides off the pin, and shorts two pins, the IC could be damaged, so don't try to do this if you have shaky hands.|
First measure the -12V on pin 11 of U4. It should measure -12V +- .2V. Then measure the +12V on U4 pin 4, it should measure +12V +- .2V.
If everything checks out to here, start the car.