Checking The Wiring
In the event of a fault at high speed, check the cable between the windshield wiper relay for high and low speed (2/90) terminal #5 and windshield wiper motor (6/1) terminal #2. Check for an open-circuit.
HINT: Check that relay (2/90) is functioning. When high speed is selected there must be 12 V at terminal #5.
In the event of a fault at low speed, check the cable between the windshield wiper relay for high and low speed (2/90) terminal #4 and windshield wiper motor (6/1) terminal #1. Check for an open-circuit.
HINT: Check that relay (2/90) is functioning. When low speed is selected there must be 12 V at terminal #4.
Check the ground supply (6/1) for windshield wiper motor terminal #4 at the ground terminal. Check for an open-circuit.
Check the cable between the relay for windshield wiper low speed and high speed (2/90) terminal #1 and the relay for windshield wiper on/off/interval (2/91) terminal #1. Check for an open-circuit.
HINT: The fault may have been caused by an open-circuit in the supply to the relay. The voltage must be 12 V at (2/90) terminal #1, (2/91) terminal #1 and at (2/91) terminal #5. Check in particular fuse 4 in the integrated relay/fusebox in the engine compartment.
Try replacing the windshield wiper motor according to MOTOR WINDSHIELD WIPER, REPLACING .
Remedy as necessary.
Other information: