On my 85 300 SD the intermittent setting is not working could it be the relay and if so where is it located?

The relay is in the black box under the hood (fuse tray). It is at the rear. There are only a couple relays there that are the same. I forget exactly where it is as it has been a couple years. It is long and rectangular. When I had my 84SD I had the same thing. I took the relay out and banged it on the bench a few times. Put it back in and my wipers worked as should. For awhile. Then I just ordered a new relay and they worked as should for the time I owned it.

Relay should be the first thing you check.

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2009 ML320 Bluetec
1985 300CD
1981 300TD

Past Mercedes
1979 300TD
1982 300TD
2000 E320 4Matic Wagon
1998 E430
1984 300SD
1980 300SD

Here is a picture of the box total of 9 relays front 5 are the same rear right is Kilma,Red one is OVP,that leaves a yellow + black one in rear is it one of them?

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Yesterday I took out every relay except the OVP, + Kilma and the wipers still worked so I do not know which relay controls the wipers I do not think it would be Kilma or OVP As I was checking fuse box I did notice blown fuse that controls F. D. + R. P. window so got those working.

I'm pretty certain it is the middle one in the rear (black).

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2009 ML320 Bluetec
1985 300CD
1981 300TD

Past Mercedes
1979 300TD
1982 300TD
2000 E320 4Matic Wagon
1998 E430
1984 300SD
1980 300SD

I believe the relay is only for the intermittent setting and does not affect operation on low and hi speeds but it has been awhile since I investigated all of this.

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2009 ML320 Bluetec
1985 300CD
1981 300TD

Past Mercedes
1979 300TD
1982 300TD
2000 E320 4Matic Wagon
1998 E430
1984 300SD
1980 300SD

The number on the relay on my car is

000 821 08 63

This has a Mercedes symbol above the above number. The location is the furthest back and to the drivers side of the fuse box just behind the silver short one, in the pic it is the middle back one. I have no idea what that big balck box on the outside does, on my car I do not have that unit. Hope this helps.

When my Intermittant wipers quit I replaced the relay and nothing happened. Replaced the wiper / multi function stalk with a new one and nothing happened. Replaced the wiper motor with the one out of my parts car and I had Intermittant wipers again.... yip yeeee.

Be very very careful pulling up on your wiper motor, it sits on 3 rubber grommets that after 20+ years are well attached to the metal of the car, the windshield is very close and the edge of the windshield can be hit by the motor mount metal if your not VERY careful. I found out the hard way, I have a half dollar "fish eye" at the very bottom of my windshield now.

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Gary
OBK #37

Thanks for the very helpful info. Graplr + Bluebird that would explain when I pulled every relay wipers still worked on low + high I did pull the middle back one and yes I have the same # on it Bluebird I will try to tap on it till I get another one I will report back if I get it fixed. Thanks-again

is relay malfunction causing problem? where is the relay located on non turbo 300cd. thanks

Strange but last time I needed them they worked must be a poor connection somewhere keeping my fingers crossed that they will work next time I need them.

Sounds like the relay is sticking. I had success (for awhile) banging mine (literally) on a work bench. It would sometimes work and sometimes not.

A new relay fixed the issue.

__________________
2009 ML320 Bluetec
1985 300CD
1981 300TD

Past Mercedes
1979 300TD
1982 300TD
2000 E320 4Matic Wagon
1998 E430
1984 300SD
1980 300SD

Thanks for the replys a fellow board member sold me an extra relay he had and wipers now work as they should.
Relay is in the middle at rear of fuse box # is 000 821 08 63 for my 85 300SD