Trouble shooting dead speedo on 85 m636

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Pat_M635csi
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Trouble shooting dead speedo on 85 m636

Post by Pat_M635csi »

So about a year ago I fired the coupe up after sitting through a typically crappy new England winter and I discovered the speedometer was dead. Tach works and so does everything else but not the speedo or odometer.

What should I check and in what order?
1985 M635CSI M88/3
1997 Z3 2.8
2010 535xi Touring w/Dinan Stage 3 upgrade
following were sold but not forgotten
2000 540it
1972 3.0CS Polaris
1972 3.0CSI Polaris
1986 735i 5sp
1983 733i
1969 2000 tilux
1972 2002 tii
1973 2002
ron
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Post by ron »

Can you re-post this in the Mechanical section please.

Thank you.
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
GRNSHRK
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Moderator will move this thread . . .

Post by GRNSHRK »

:mrgreen:
:mrgreen:
Bobbo
1980 633 CSi Cypress Green/Pearl Beige
2017 X5 M Sport Xdrive 35i Carbon Black/Ivory White
2005 330 Ci ZHP Cabrio Imola Red/Bone/Black
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ron
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Post by ron »

Bobbo, How did you move it?

I'm unable to moderate in the "Workshop" section. Have mentioned this to Brian before.

Best.

Ron.
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
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Brucey
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Post by Brucey »

first thing is to check the pulse generator at the diff and the wiring to it.

IIRC you should test for volts first; one wire should read ~12V. The other wire should look like a ground connection.

The pulse generator should look like a switch that goes open-closed-open-closed- etc as the road wheels (and propshaft) are turning.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Soperman
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Post by Soperman »

I had a similar issue once. Simple enough fix, it turned out to be an under-bonnet fuse number 12.
E24 M635CSi
GRNSHRK
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Moderating the Workshop . . .

Post by GRNSHRK »

I'm unable to moderate in the "Workshop" section. Have mentioned this to Brian before.
Hey Ron, appears that there are no moderators for the Workshop, strange :-k

Lemme ping my bro the true web master, let's see what he's got to say about that :-?

:mrgreen:
:mrgreen:
Bobbo
1980 633 CSi Cypress Green/Pearl Beige
2017 X5 M Sport Xdrive 35i Carbon Black/Ivory White
2005 330 Ci ZHP Cabrio Imola Red/Bone/Black
Image
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Pat_M635csi
Posts: 50
Joined: Wed Dec 11, 2013 9:28 pm
Location: Boston

Speedo - Thanks

Post by Pat_M635csi »

I will take a shot at it this weekend
1985 M635CSI M88/3
1997 Z3 2.8
2010 535xi Touring w/Dinan Stage 3 upgrade
following were sold but not forgotten
2000 540it
1972 3.0CS Polaris
1972 3.0CSI Polaris
1986 735i 5sp
1983 733i
1969 2000 tilux
1972 2002 tii
1973 2002
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