Legacy 990 Problems

I don't think the headlight should come on before startup for most Legacy locomotives.

As for the GP35, I doubt that's the sound board, sounds more like the RCMC Receiver may have become dislodged from the RCMC main board, it's a fairly common issue.

I have seen a 990 base fail with very strange symptoms.   I had my TMCC command viewer software active so I observed illogical commands being transmitted by the base out it's serial port and LCS WiFi.  What was broadcast to the track is unknown but if it was the same bogus commands as transmitted out the serial port, then it would account for loco failures.  Several engines would not start or run, others seemed OK.   I replaced the base and all was good again.  Firmware/memory/hardware failure is suspected.

Since you have engines that start in conventional, I would suspect the signal output from the base.  If you have a TMCC1 base,  unhook the 990 and try the TMCC1 base's output to the track.  If the loco still won't run under TMCC1 command, then follow GRJ's advice and re-seat the receiver board.

Dale Manquen's archives describe how to test the 990 signal strength with a multimeter.  I found that test to be of value when  verifying poor signal strength on large layouts.  A good signal strength (i.e. voltage), however, does not ensure that good information is being broadcast from the base.  If your locos run with a different base, then send the 990 back to Lionel.

gunrunnerjohn posted:

I don't think the headlight should come on before startup for most Legacy locomotives.

As for the GP35, I doubt that's the sound board, sounds more like the RCMC Receiver may have become dislodged from the RCMC main board, it's a fairly common issue.

My bad, the engine light comes on after entering the engine ID.  Talking about a VL  Hudson, light  will come on and nothing else.

GP 35: Is it possible for a non-mechanical person to fix or  replace the RCMC board? Worst that can happen is a non working engine

Dale Manquen's archives:  How do I find them, I did purchase his wiring hook up several years ago.

Brent

I know its sounds simplistic, but did you verify the connection between your base and the track has a clean 100% tight connection?  I have seen so many threads and its just a bad connection. Oxidation that one day makes everything stop working or not work correctly.

Seems odd 2 engines would go at once.  Do you have other legacy engines that work ok?

Thanks, cleaned all connections , engines still do not work

Brent

Dale Manquen's archives are at trainfacts.com.   Try to find a different working base for testing.

BReece posted:

GP 35: Is it possible for a non-mechanical person to fix or  replace the RCMC board? Worst that can happen is a non working engine

Anything's possible, but truthfully I'd let someone look at it.  You'll pay $120 for an RCMC, and if you screw it up, you have a big repair bill and a non-working locomotive.  You can at least verify if the small TMCC receiver is properly seated on the larger RCMC, that part you should be able to do.

BReece posted:

Thanks, cleaned all connections , engines still do not work

Brent

Has anything changed since you last ran trains? Its the command base wire still secure? Is the base plugged into a powerstrip? different outlet etc?

There have been reports of the nut on the command base wire post inside the base coming loose causing issues as well.