hi, i am wondering if anyone can help

my old 520d touring 58 plate LCi had an issue with its wiper arm mechanism - the arms basically fell apart due to worn out bearings
i replaced the arms of the mechanism and its good as new now - but seems to have developed a problem with the windscreen washers at the exact same time - as these no longer work

the car is old so i though the pump was likely just worn out - but thought it a bit odd that it happened at the same time as the wiper fault
so today i took the wheel off an wheel arch liner out and got at the pump - only to find the same pump feeds both the front and the rear washers - and the rear washers are working fine ????

i had read there is a resettable electronic "fuse" on the washer pump circuit - but no actual fuse - but since the motor runs when the rear washers are activated it cannot be that

i connected a multimeter to the plug on the pump and it showed a small voltage briefly when the wiper stalk was pushed away from you for rear washers - but not when pulled towards you for the front

i see there are electrical wires going to connectors on each of the washer jets - what are these for? could they be related to the problem ( wondering if they got a whack when the wiper arms went berserk and tried to mash themselves together )

has any one else seen this - where the pump works fine - and the rear washers work - but not the front ?

which module controls the washers ?

much appreciated !!

 

It would help immensely if you could read the DTC codes.

 

i would love to be able to do that

in fact i have an old copy of INSTA from a few years ago when i was messing around with a faulty Lights Module - and have the cable somewhere - but i don't have a suitable laptop to run it on at the moment.

i am in Telford 5mins from the M54 - and have top notch espresso on tap if anyone local has a suitable setup and fancies helping out

 

I'd buy a BMW code reader instead of messing with ISTA. Don't tell @seanjordan20 I said that though.

 

as i say - i don't have either option right now-
surely for something simple like the washers - there is only some many things it can be - and there must be some way of figuring out which

the pump itself is fine - it only has 2 wires and i can see that whatever module sends voltage to it is not sending it - so presumably its either that module - or possibly the switch in the stalk

can we not figure out which without a reader ??

 

Could be the stalk, module or wiring. You will need a BMW reader to rule out the module.

 

OK - which module controls the washer motor

 

Wiper/Washer Control Module.

 

I did some googling and it seems its controlled by the KBM - Basic Body Control Module - living in the glove box area -
stalk talks to KBM - and KBM activates the washer motor

https://www.meeknet.co.uk/e64/tis_ro...e%20System.pdf

the wiring works - as the pump runs when the rear wiper is activated - a used KBM is a fraction of the price of a reader - so i may go that route

 

A reader cost $44. Using one stops you from throwing parts at the problem. KBM is part of the scheme, but the washer/wiper module is involved too. I am not wronging you, if you want to throw parts, that's your choice. You'll also have to code it.