The electric antenna has a mechanical timer on the winding drum. This limits the physical amount of time it runs. If there is any slippage on the drum, that antenna will not fully extend/retract.

You can get a scenario where the the antenna will not fully retract if you do not get the nylon pigtail engaged soon enough.

You really need two people to set up the antenna. Have one person in the car ready to operate the switch, and have the nylon pigtail fully pushed into the drum, so there is no slack when the motor starts the retract cycle.

You can also fool the antenna position by holding the antenna in when it starts the raise cycle.

The is also an adjustment on the motor clutch for dealing with slippage.

As a side note, I've seen both smooth and toothed cables, not sure to what effect a substitution such as you performed will affect the operation....

Jim

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14 E250 BlueTEC black. 45k miles
95 E320 Cabriolet Emerald green 66k miles
94 E320 Cabriolet Emerald green 152k miles
85 300TD 4 spd man, euro bumpers and lights, 15" Pentas dark blue 274k miles