Pagoda SL Group

W113 Pagoda SL Group => Electrical and Instruments => Topic started by: ptooner on October 21, 2010, 20:00:20

Title: 230SL idle solenoid
Post by: ptooner on October 21, 2010, 20:00:20

HI guys, I'm new here and have found a world of good info.  Unfortunately I haven't cured the problem.  I have a 65 230SL with auto and a/c.  Anytime the ignition is on, the idle kick up solenoid is energized.   I'm referring to the one on top of the intake manifold that pushes up the linkage for higher idle when the car is in gear or the a/c is on.  I could ignore this problem but it seems to be related to the other more serious problem with the transmission three position solenoid.  It works as advertised except that once it goes into kick down mode it will only come out if you switch off the engine.  Something is holding the power on once it is engaged.  The color schematic doesn't show these parts so far as I can tell and I have tried to interpolate from the 280SL diagram but am not sure they are the same.  Any suggestions as to how to proceed?  FWIW, the wires on the idle solenoid are green and green/black I think.  Thanks for any help.
Gerry

Title: Re: 230SL idle solenoid
Post by: Peter van Es on October 21, 2010, 20:35:16

Did you check the wiring diagram in the middle of this page in the Tech Manual? http://www.sl113.org/wiki/Automatic/Start

Peter

Title: Re: 230SL idle solenoid
Post by: ptooner on October 21, 2010, 20:40:46

Yes I did.  The idle solenoid (item 6) has a wire going to a fuse and the other going to never never land.  I did, however, determine that if I disconnect one of the wires from this solenoid the transmission operates as it should.
Gerry

Title: Re: 230SL idle solenoid
Post by: graphic66 on October 21, 2010, 22:17:24

The idle solonoid is switched on by pressure switches on the transmission, one for forward, one for reverse. The solonoid is provided with constant positive power and the solonoid is activated by grounding at the transmission. The wire goes to the tranny, and hooks to both switches. You could have a bad switch, or a wire shorting to ground somewhere. You will need to use an electric meter of some sort to find out what is wrong. 

Title: Re: 230SL idle solenoid
Post by: ptooner on October 22, 2010, 01:34:45

If I understand correctly you are saying that the two pressure switches provide a ground when the transmission is in gear.  If that is correct, then either I have a bad switch or a grounded wire between the solenoid and the transmission.  I'll check on that.  I don't understand why that would effect the shifting, though.  Today I disconnected the red wire on the idle solenoid and now the transmission works correctly.  That is it goes into kickdown and out as it should.  I guess I now must troubleshoot the wire from the idle solenoid to the transmission pressure switches.  Thanks for the info as I had no idea where the wire went from the idle solenoid.
Gerry

Title: Re: 230SL idle solenoid
Post by: glenn on October 22, 2010, 03:10:20

ptooner, (As I have said before) we need the correct wiring diagram and Joe's 'plainin of the correct operation.

Title: Re: 230SL idle solenoid
Post by: graphic66 on October 29, 2010, 14:45:18

http://www.mercedesdismantlers.com/16BoltInstallationInstructions.html  Wiring diagram link

Title: Re: 230SL idle solenoid
Post by: ptooner on February 04, 2011, 00:02:22

Quote from: glenn on October 22, 2010, 03:10:20

ptooner, (As I have said before) we need the correct wiring diagram and Joe's 'plainin of the correct operation.

Sorry I was away quite a while, but anyone still reading - the problem turned out to be that the rebuilt transmission has no pressure switches or provisions for any.  Disconnecting the wire that should go to there seems to have fixed all the problems and the car now shifts as it's supposed to.

Gerry