6-28389 ICG GP30 smoke unit resistor does not heat up. Tested resistor independent of engine power unit it heats up. Reassembled smoke unit fired up engine in command mode, fan comes on but resistor does not get hot. What gives?
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You might be able to glean what to test next from:
https://ogrforum.ogaugerr.com/...56#80128401230598356
and go down about 2/3 to see the document on smoke unit components; especially the 5 pin receptcale on the PCB board that serves the plug coming from a RCMC board.
Can you measure the voltage at the smoke unit resistor terminals? Should be the screw heads either side of the funnel.
Forgot to mention the thermistor that sits along side the heating resistor.
RickM46 posted:Forgot to mention the thermistor that sits along side the heating resistor.
I don't think that this particular smoke unit has a thermistor. In the online photos of the PCB, there are no mountings for one. Also I think that it pre-dates the Legacy/Vision models that were equipped with thermistors.
Are you sure that somehow the smoke setting has not been set to "off"? Have you tried an engine reset per the manual?
Hancock52 posted:RickM46 posted:Forgot to mention the thermistor that sits along side the heating resistor.
I don't think that this particular smoke unit has a thermistor. In the online photos of the PCB, there are no mountings for one. Also I think that it pre-dates the Legacy/Vision models that were equipped with thermistors.
Are you sure that somehow the smoke setting has not been set to "off"? Have you tried an engine reset per the manual?
Hancock52 you are correct this particular version of the smoke unit predates the use of a thermistor. I have tried a reset still no smoke. I'm beginning to think the resistor is not getting power from the RCMC board through the four pin harness to the smoke PCB, fan however is working.
Each of those 4 pins might be labeled on the PCB board - just guessing, one is for the fan, one for the heater, one is ground, don't know the name of the last one. Maybe there is a way to put a meter to them to test for voltage.
RickM46 checked continuity which is OK but the heater is not getting voltage from the RCMC to the smoke PCB pins. Hope this doesn' mean a new RCMC board is needed they don't come cheap.
When Mike R. fixed the smoke units and RCMC on my Big Boy, he replaced the RCMC and its cost was around $120 plus labor. If there is no voltage coming to the heater, have you checked the continuity of the harness from the RCMC to the PCB?
Have continuity from RCMC to PCB just not getting voltage
If you want to replace the RCMC, I believe you have to call Lionel to get another; the Big Boy RCMC cannot be ordered online. Maybe someone on the forum knows if yours can be fixed or if a dealer has one.
One last thing, can you disconnect the plugs and then re-seat them; can you pull the RCMC and then re-seat it?
Pulled connectors and RCMC and reseated still be no joy (smoke). Looks like perhaps a new RCMC is in the offing.
Let us know if the RCMC replacement solved the problem.