Swapping combo relay from a 76 530i to a 77 530i ?

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canada karl
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Swapping combo relay from a 76 530i to a 77 530i ?

Post by canada karl »

Can I do this without an issue. The relays look different,the 76 has the metal casing and the 77 they went to a black plastic case and the part #'s are different but I suppose they should perform the same function? Haven't pulled the wiring connectors out yet on the 77 to see if they match up.
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
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Robert Bondi
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Re: Swapping combo relay from a 76 530i to a 77 530i ?

Post by Robert Bondi »

I think it would work, but that's a guess. I suspect the black plastic case is more an indicator of much more recent manufacturing than a different part and possibly also a part number supercede to explain that difference too. I can tell you my 77 530i originally had a metal case combo relay too. It's worth trying if pin count, size, orientation ,etc.... match.

Also check the obvious like the fuse box and just unplugging and reseating various electrical connectors is often revealing.
Robert
77 530i
77 Euro 528
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Mike W.
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Re: Swapping combo relay from a 76 530i to a 77 530i ?

Post by Mike W. »

I thought all 530s were the same. 528s I know are different. But what does Realoem say? It's not perfect, but it's an invaluable resource that's usually right.

Also as Robert said, check pinout by number and location.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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maybeillbuyit
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Re: Swapping combo relay from a 76 530i to a 77 530i ?

Post by maybeillbuyit »

Robert Bondi wrote: Sun Jul 07, 2019 7:02 pm I think it would work, but that's a guess. I suspect the black plastic case is more an indicator of much more recent manufacturing than a different part and possibly also a part number supercede to explain that difference too. I can tell you my 77 530i originally had a metal case combo relay too. It's worth trying if pin count, size, orientation ,etc.... match.

Also check the obvious like the fuse box and just unplugging and reseating various electrical connectors is often revealing.
I agree, my 77 had a metal case. I seem to remember swapping a different part no combo relay into my car at some point. The pins were the same etc and it seemed to work fine. I have several combos from various years etc so I can't remember one it was now .
But if the pins are the same, orientation etc it should work. Its really just two switches.
1977 530i another project
1979 635csi Euro "project"
1987 635csi
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Lock
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Re: Swapping combo relay from a 76 530i to a 77 530i ?

Post by Lock »

My '79 528i has the black plastic combo, but the PO also supplied the original (not working) metal case combo relay. I soldered up a broken link but it still doesn't work.

The black plastic has one extra leg for the 1980+ electric aux air valve (same output as fuel pump), which my car doesn't have but besides that it's identical.
1979 528i - M30B34 with 9.5:1 B35 pistons, 5-speed conversion G260/6, e28 rear subframe, e34 LSD 3.9:1, glass sunroof, e30 elec speedo, cruise control
canada karl
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Joined: Tue Jan 06, 2009 3:50 pm

Re: Swapping combo relay from a 76 530i to a 77 530i ?

Post by canada karl »

Well I did take the black plastic relay out of the 77 and installed it in the 76 and it fired right up so it's all good. :D
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
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