The Pennsy 18000 switcher I just bought has a whistle, bell and steam sound. With the steam sound turned off, the whistle still works. Although my Post-war ZW could be finicky. The whistle control was working just fine until today. Now when I press the whistle control, on the transformer, the loco goes through it's E-unit sequence with each movement of the whistle control button.
Any suggestions ?
First, test another engine...
Second, swap AU and DU... (Each side has its own rectifier & switch setup).
If you still believe the switch/rectifier unit to be at fault, take the cover off and use some tv tuner cleaner or CRC 2-26 and clean the switch contacts.
Lastly, you can replace the rectifier disc with new disc or solid state diodes 1N1190AR. See https://ogrforum.ogaugerr.com/...71#77875232795593471
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