First off thanks to everyone on this site for indispensable help getting my 1970 280SL back on the road after a long restoration process. Second, I have read and re-read, and re-re-read every post and material in the tech manual regarding the ww wiper function.
As stated in the subject line, wipers do not turn off.
I suspect that my multi-function swith is not working properly and plan to send off to Sead but once I do that, I can't do any more diagnosis until it comes back.
Working today I discovered, by accident, something that seems strange. I have been unplugging and plugging in the connector for the multi-function switch under the dash. I didn't realize it was unplugged and when I turned on the ignition switch I got 12 volts at the wiper motor at both in 4 and pin 1. We know that pin 4 is supposed to get 12V straight from fuse 2 so that makes sense. But how did it get 12 volts at motor pin 1 with the mult-function switch unplugged?
Then I unplugged the connctor at the WW relay and now get 12v only at motor pin 4. I thought the wiper motor was turned on and off with the multi-function switch.
As an aside, the park feature of the wiper motor works correctly.
If the WW relay connector is plugged in to the relay, it looks like there is 12v at relay pin 56b. In order to get 12v to wiper motor pin 1, I'm guessing that it is gettting that 12v from 56b on the relay to pin 56 on the relay. But if this is correct, it seems like the motor will always run.
So, how is current supposed to be shut off to pin 56 at the relay? And is this even the right question?
If the multi-function switch connector is connected under the dash, it does pretty much the same thing and pushing on the switch does nothing, which is why I suspected the multi-function switch. But if it performs the same way with the multi-function switch disconnected, then it seems as though it may not be the switch.
I have checked and rechecked the wiring colors and am as sure as I can be that they are correct and I can provide them if that helps.
Thanks in advance for any insight into this.