BMW E38 wipers and washers not working
Why do the E38 wipers work intermittently or stay in the up position?
The wiper relays (K36 and K37) are in the electronics box under the plastic cover on the right side of the engine bay. Moisture oxidises the relay pins. Pull the relays out, clean the sockets and check the connection points first.
The wipers do not work even though the relays, fuses and motor are fine
The relays are controlled by the basic module (Basic Module), which is under the dashboard in front of the glove box. The cause can be a broken wire in the relay base or loss of the end-position sensor signal. Then the motor stops after 16 seconds and is locked for 3 minutes. Check the wiring before replacing the basic module.
Why do the windscreen or headlight washers not work?
The windscreen washer's power comes directly from the basic module. The control of the headlight and power washers goes through a separate relay unit behind the glove box and is protected by fuse F4. The wiring bundle of the front passenger's inner wing can chafe against the sheet metal and break; check the wiring and the pumps.