Zeusmorg,
Lack of reply is always frustrating. I believe that you will get a replacement controller from GoldenMotor but unfortunately my believes does not help you, but keeping this thread warm does
Anyway, at least a good fault diagnostic procedure for the BAC series controllers has come out of this (with the help from you and
stl_recum):
A) Controller diagnostic
1. Connect only battery to the controller. Remember to connect both main + terminal and the small red lead (soft switch lead) to + on battery
2. Power up the controller using the battery key switch.
3. Measure voltage between + battery terminal and GND on controller. Verify that you have at least nominal battery, if not go to chart B)
4. Measure voltage between + 5V terminal and GND on controller. Verify that you get about 5V. Replace controller if voltage is less than 4V.
5. Power down the controller.
6. Now connect the three motor power leads (the big wires)
7. Power up the controller.
8. Check the +5 and GND terminal on the controller.
9. Do you get about +5 volts. If yes continue, if not replace or fix motor.
10. Power down the controller.
11. Now plug in the Hall sensor connector from the motor (the small wires).
12. Power up the controller.
13. Check the +5 and GND terminal on the controller.
14. Do you get about +5 volts. If yes continue, if not replace or fix motor.
15. Power down the controller.
16. Now plug in the throttle connector.
17. Power up the controller.
18. Check the +5 and GND terminal on the controller.
19. Do you get about +5 volts. If yes continue, if not replace or fix throttle.
20. Power down the controller.
21. Now plug in the horn connector.
22. Power up the controller.
23. Listen to any beeps from the horn. If any beeps are heard, use the Controller manual to diagnose any remaining controller errors.
B) GoldenMotor battery/Power diagnostic
1. Preparation: Disconnect battery from controller. Turn on battery power key switch. Measure voltage directly on battery connector on battery. If less than nominal voltage recharge battery then continue.
2. Connect a resistive load to battery that uses more than 0,1A and less than 1A. A 50 to 100 ohm power resistor that can handle the power is nice. If you do not have a suitable power resistor, an incadescent lamp (120V & 40W / 230V 75W) is a suitable substitue.
3. Measure voltage over load. Is it nominal voltage or more the battery and connections are working.
4. Measure voltage over load. Is it less than 1V then power up the battery charger and connect it to the charger input on the battery and repeat measurement. If the voltage is much higher now, the charger supplies too low voltage (verify) or battery is defect.
5. Disconnect charger and load.
6. If there is a glass fuse acessible from the outside of the battery casing, remove it and measure its resistance. Replace fuse if it is not fully shorted (much less than 1 ohm) and go to step 2.
7. If there is a resettable fuse acessible inside a rubber diaphragm, try to push it in to reset in case it has been trigged. If this could be the case, go to step 2.
8. Check battery power cable. If it is OK open battery connector end carefully. Avoid damaging wires or making shorts - that could set your house on fire
9. Reconnect resistive load to battery.
10. Measure voltage over load. If it is different now you probably have a bad connection somewhere - look for loose connectors, loose crimps and bad soldering.
11. Measure voltage drop over key switch and fuse. Make sure the switch is turned on. If there is a real voltage drop (typically more than 100 mV) replace or fix the part.
12. Disconnect load.
13. Put on battery lid carefully, verify that no cables are caught between housing and lid and observe correct position of lid.
14. Turn on power switch.
15. Measure voltage directly on battery connector
14. Reconnect load.
15. Measure voltage over load.
16. If battery is still not supplying any power to the load replace battery.