peugot 405 washers wired thru ECU?

my windscreen washers on my 2003 405 hdi have failed. washer pump is ok when tested, the switch/stalk is good too. The garage tell me wiring passes thru the ECU. Can i avoid buying a replacement ECU? Possibly by wiring washers direct to another aftermarket switch thus avoiding the ECU? any advice really appreciated, thank you