[STEVE]

STEVE on September 1, 2020 at 8:16 am #20165

Dennis,
Thanks for adding clarification to this post.
It’s greatly appreciated,
Steve

[Dennis]

Dennis on September 1, 2020 at 6:10 am #20163

The small diodes in the Annunciator Panel have very little to do with whether the individual lamps light or not when appropriate. Those diodes primarily support the TEST function in that they allow power to the lamp for testing of the lamp itself, not the entire system.

The diode that controls the lighting of the ALT lamp in normal operation is a very large diode that is located under the rear seat. Look for connection problems there.

Also, note that the lamp for the ALT indicator is a low voltage lamp. It is not the same as the OIL or VAC lamp. The actual voltage rating of the ALT lamp depends on the voltage of your ship’s battery. Check your parts manual for the proper lamp.

VFRs,

[STEVE]

STEVE on April 15, 2020 at 11:07 am #19848

The diode and the resistor is in the annunciator panel itself. The resistor is 50 ohms 6.5W.
The resistor part number is 484-494 (VC5E).
The diode part number is 456-714 (1N4001).
I have attached a drawing to better illustrate the set up.

[Robert]

Robert on April 12, 2020 at 12:33 pm #19843

I own a 1979 PA28-161 Warrior II. For the last year now the alternator warning light does not turn on when the master is turned on without engine running except on intermittent occasions. The bulb always lights using the test button. The operation handbook circuit diagram shows the light bulb circuit goes though a diode and resistor to ground and is back biased to turn it off only when the alternator in running. I suspect a bad connection since it functions sometimes. Would you know the location of the diode and resistor and how to access it? Also the value of the resistor. Hopefully not too hard to access.