issues automating button press (contact shorting) with relay

[/RaspberryPi]

Hi all,
I'm attempting to automate starting the cleaning cycle of a Braun Clean and Charge station (this appears to be the same model here)
I'm using a 4 relay module (The ebay listing) to allow me to bridge the contacts which the original button used to allow me to start the cleaning cycle.
This is the Ifixit photo for the board the station has, you will see at the center top of the board there are two sets of semicircle contacts the upper set is used by the button and when shorted for a couple of seconds will start the cleaning process. https://guide-images.cdn.ifixit.com/igi ... vtf.medium
I've been running tests with the relay and have been able to activate the relay (atleast the indicator LED for the relay anyway) using;
import RPi.GPIO as GPIO import time in1 = 18 if __name__ == "__main__": GPIO.setmode(GPIO.BOARD) GPIO.setup(in1, GPIO.OUT) GPIO.output(in1, True) time.sleep(3) GPIO.output(in1, False) the wires used to short the contacts are connected to the NO and COM terminals on relay 1 with the control wire for relay 1 connected to pin 18 (Board numbering).
When I close the relay nothing happened with the cleaning station but the relay indicator light did still change, as a test I changed the wire connected to NO to NC where the result was the opposite whether the GPIO was true or false it was permanently shorted which to me suggests the relay isn't actually switching? I have also tested using the 5v+ wire of a Microusb cable since which had similar results.
I wondered if there was sensitivity regarding wire length so I tested shorting the contacts with two wires which had the desired effect.
I'm using a RPI 3B+
Would anyone have any suggestions regarding what could be the issue/workarounds?
Apologies if I've missed out any relevant information.

submitted by /u/jordanws18
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