86 560SEL continues running after key removed

[qweasdzxc]

With the battery connected everything goes on without the key can hear the fuel pump working etc. The key will turn the starter and then start the car but when i remove it everything keeps going. I was thinking maybe just the ignition switch? But it must still be working if its putting the starter on. Or maybe a hot wire from the alternator or starter is powering everything still? Just looking for some suggestions on a fix before i order the switch.

[sixto]

Sounds like the key switch goes between run and start but not back to accessory or off. Unless you have aftermarket starter inhibit or other custom wiring gone wonky it has to be a bad key switch.

Sixto
83 300SD
98 E320 wagon

[Frank Reiner]

Originally Posted by qweasdzxc

With the battery connected everything goes on without the key can hear the fuel pump working etc. The key will turn the starter and then start the car but when i remove it everything keeps going. I was thinking maybe just the ignition switch? But it must still be working if its putting the starter on. Or maybe a hot wire from the alternator or starter is powering everything still? Just looking for some suggestions on a fix before i order the switch.

Remove both wires (large red & small blue) from the alternator, and start engine. If it will now shut off with the key switch, look to a diode problem; if not, go with sixto.

[qweasdzxc]

Sorry for the late response i had to go out all day yesterday. I will check the wires on the alternator and decide if its the switch after that. Thanks for all the help ill report back with what works.

[qweasdzxc]

I went and checked and it seems to be the switch i ordered a new one. Before i start taking things apart is there some trick to getting this switch out? Such as turn the key in a ceritan position to unlock it? Or how would i go about it?

[Mighty190]

If its like a 201 or 124 you need the key to get it out. You will turn it to a position and then use a pin. Otherwise you end up having to drill it out (very difficult) or find a junkyard column with a key.

Ignition Cylinder Lock Removal

[tyl604]

**************'s Kent Bergsma also has a video showing how to do this. For some reason it just turned up in my email; no idea why.

[qweasdzxc]

I took everything apart and got the switch out and changed it still having the problem.

http://www.pelicanparts.com/catalog/SuperCat/3481/MBZ_3481_ELSWCH_pg3.htm#item8
is the switch i bought.

There are a few differences in the switch if you look at the 1 i linked in the center in the plastic slit there is a rotor on the old 1 which doesn't seem to pull out. The old 1 is also about a 1/4 inch deeper.

Could this be the wrong switch or is my problem somewhere else?

I just looked around and it seems they used the same switch for most models and future years..There really is only one way the switch can go together so im assuming my problem is something else

[sixto]

Did you try the switch without the key tumbler? Maybe it's the key tumbler that's not engaging the switch properly. Also, try again what Frank Reiner suggested.

Sixto
83 300SD
98 E320 wagon

[qweasdzxc]

I tried the key without the tumble and the problem persists i also disconnected the alternator again as Frank suggested with no luck there either. Could there be some relay or a fuse somewhere that's leading back to it somehow? Any more help would be greatly appreciated im a little lost at this point.

[sixto]

Is it possible there were issues with the fuel pump relay that someone patched by rewiring? Is there an after market security system with starter cutout that's gone wonky?



Sixto
83 300SD
98 E320 wagon

[Frank Reiner]

q:

Since there does not appear to be a problem in either the alternator or the key switch, try pulling the Over Voltage Protection relay (OVP). The OVP can back-feed into the ignition circuit, as one of the circuits within the OVP is in parallel with switched power, but is always hot.

[qweasdzxc]

The fuel pump relay went out maybe a month ago and i changed it has been working fine and the car has no security system as far as i know. This OVP relay where would i find it? There are 2 relays on each side of the fuel pump relay 1 is smaller with a fuse on it the other im not even sure if it is a relay its just a circuit board with a cover over it. Also now that i think about it even if i disconnect the ignition switch from the harness everything still comes on when i hook up the battery so that would tell me my problem is somewhere else i believe. The relay next to the fuel pump relay has a 10amp fuse on the top and is what i believe to be the OVP i took it out and the car still started and stayed on without the key.

[Frank Reiner]

q:

Two more tests:
1) Remove relay K17 (Air Injection). It is located in the fuse and relay box; there are two rows of "ice cube" relays, four in the left-most row, and two or three in the next row to the right. K17 is the second from the back in the second row.
2) Remove the fuel pump relay, and jumper the sockets that correspond to pins 7 & 8. The fuel pumps will run continuously until jumper is removed.

Try starting and shut off in each of these situations.

[qweasdzxc]

I tried both of those and the fuel pump did run continuous you as you said neither of them worked sadly tho. The cube relays in mine if your standing infront of the car the row of 2 is on the left with a row of 4 next to it on the right. However as i wasn't sure i tried starting and stopping with all 6 of the cube relays removed 1 at a time.

Also i dont know if this changes anything but when the battery is connected the fuel pump is not actually running as i said before there was some slight confusion at first i guess and since then i was just under the assumption it was running all the time but i checked myself and it is not