oil level indicator on
 

on my 1986 500sel euro i am having some difficult issues with the oil level indicator light. it will not go off!! i do not rely on this for anything at all, i am just one of those people that likes things that work correctly. when i first bought the car a year or so ago the light was on, i removed the subpan replaced the level sensor and all was well for about 2 months. then the light came back on. at first i thought it was low oil so i added some, light was still on. i disconnected the wire where it goes in to the block, light was still on. i unhokked the connection at the master cylinder that goes to the starter, oil pressure sensor and oil level sensor, light was still on!! so i troed a few different clusters newer and older with the same result. the only time i can get the light to go off is when i unplug the 8 pin connector on the back of the speedometer:silly: there is a good solid circuit from the oil level sender plug up to the round connector, it seems to me that something is backfeeding at that plug. but to my knowledge it has not been tampered with.
is there something i am over looking? any advice would be appreciated.

Have you rechecked that sender in the pan? My SDL would have the low oil level light come on constantly, $18 later it's off for good (new sender :D ).

i have unplugged the sensor wire from the firewall down to the sensor, completely eliminating the wiring from the firewall forward, and the light is still on.

Hrm, strange. :confused:

it would be nice to have the proper wiring diagram, i cannot be sure 100% it is same as a U.S. model

i did some reaserch and found the 560 and 500 are similar for the round plug, but no where alike for the square plug on back of the odometer. see below
if anyone knows what #5 grey/violet and #8 grey/blue and #15 brown green are that would be helpful, those colors aren't on the US models.

Round pin plug
1. Dark green- coolant temp gauge
2. Blue/black- fuel gauge
3. Blue/green- fuel gauge reserve
4. Brown/black- oil level sensor
5. Grey/violet-
6. White- high beam indicator
7. Black/pink- power fuse #7
8. Grey/blue-
9. Blue- charge indicator
10. Brown/white- brake fluid level, parking brake indicator
11. Brown/red- pad wear indicator
12. Black/purple- power from pin #7
13. Brown/yellow- coolant level indicator
14. Brown/blue- windshield washer fluid level
15. Brown/green-


Square plug on back of odometer

1. Brown/green
2. Grey/purple
3. Black/green
4. Brown
5. Black/grey
6. White
7. Grey/blue
8. Black/pink

when you unplugged the wire to the sensor, you grounded it right?

If you ground the wire at the sensor the light will go off. Mine does not work either and the previous owner or a tech had cut back part of the wire sheath and attached a ground to it, just wrapped up and taped. Cheesy but it works still and I have had it for two years.

Fixed
 

thanks guys the last two hit it head on!! i was assuming it was the same as the coolant light or the washer bottle, when the sensors there are defective unplugging them turns the light off. i was also not thinking of the sensor because it is brand new. i guess no matter how long we work on these car we can always learn somthing. i am a little embarassed since it was something so simple. thanks again