Problem with headlights

[petertg]

I have an old Lima locomotive (RE620) (Re 6/6) nº 11603 which is nigh on 40 years old. I have fitted a Zimo MX632 decoder and, after various problems, namely dirt on wheels and a faulty connection, I have managed to get it to run. However, I still have a problem which is that immediately power is applied, before addressing the locomotive, the front headlight comes on and, after the loco is addressed, it stays on independently of F0 control or direction of running. The rear headlight comes on depending on the vehicle direction and can be switched on and off.. What can the reason for this be?

There are no diodes or resistors installed. The bulbs are insulated from the chassis, because I cut the blue decoder lead and neither light comes on. I assume that on these models the motor is at the rear end and that the left and right hand motor terminals are such that the left hand one is at the rear side of the motor towards the rear end and the right hand one is at the front side, but the lights do not seem to be in accordance with this. Bit 0 of CV29 is 0. The yellow and white decoder leads have been installed according to diagram.

All help will be appreciated.

[Austrag]

I suspect that the "bulbs" have ruined the decoder. They should have been changed to LEDs.