If the windshield wipers do not work or start acting weird on your 5 Series, the simplest thing you can check or change is the Windshield Wiper Relay/Switch. The relay is located under the passenger side microfilter box and easy to get to.
This DIY applies to all E39 5 Series made after 2001. I believe the procedure is the same for earlier E39 models but the relay(s) are different.
Tools:
- 6mm hex bit socket and ratchet
- Extension (Optional)
- Dielectric Grease (Optional)
- Flat head screwdriver
Parts:
- BMW Multi Purpose 7-Prong Relay
- Part # 61368384505
- It is brown colored
Steps:
- Remove passenger side microfilter box.
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| Driver side box is pictured. Remove the Passenger side box. |
- Use a flat head screwdriver and push down on plastic tabs to disconnect air duct. (Red)
- Unclip metal latch holding air filter cover. (Purple)
- Remove air filter tray cover. (Yellow)
- Remove cabin micro filter.
- Remove rubber trim/weather stripping around cabin filter tray.
- Squeeze and remove metal clip from screw holding tray to body of vehicle. (Blue)
- Lift and remove cabin air tray.
- Remove relay box cover.
- Remove four bolts (green) using 6mm hex bit socket and ratchet.
- Remove relay box cover
- There are two small plastic tabs/clips on the back of the cover that attaches to the relay box. Gently work the cover until it comes free, if the plastic is so brittle the clips may break which is okay since the cover is held by the other four bolts.
- Remove and replace old relay.
- Relay location is circled in red.
- Simply pull out and insert the relay. There is only one way the relay can be inserted and is dummy proof.
- Optional: Apply dielectric grease to the relay pins to prevent corrosion or water damage.
- Check and see if windshield wipers are operating correctly.
- Re-installation is the opposite of removal steps.
- Re-attach relay box cover.
- Install four 6mm hex bolts.
- Reinstall microfilter box with rubber trim, clips, and reattach air tube.
Notes:
The relay box also contains the fuel injector, DME, Auxiliary Fan, Air Pump, ABS, and Auxiliary Fan Stage 3 relays. This DIY has the exact same steps if you need to access these relays and fuses.
If the windshield wipers are still not operational or acting funny, it may be the wiper switch on the driving column, wiper assembly, or wiper motor that is not working. The relay is the easiest and cheapest thing to check first.
Make sure relay box cover is snug and there are no cracks so there is no water coming into the relay box.
If you don't want to spend money on a new relay, you can try cleaning the relay contacts and see if the windshield wipers work.
Make sure relay box cover is snug and there are no cracks so there is no water coming into the relay box.
If you don't want to spend money on a new relay, you can try cleaning the relay contacts and see if the windshield wipers work.
