I have a 1986 560sl, I think that my over volt relay is giving me
trouble but have become frustrated in the process of what I thought was
a good diagnosis fallowed by a simple repair (replacing the over volt
relay). Well here is the story. My ABS light came on and the engine
idle went to 1500 RPM. After study I concluded that the over volt
relay had gone kuput. After locating it I tapped on it and was able to
get the problem to go away. I could start engine and the ABS light
goes out and engine idles slow. After a couple of restarts the problem
reappears but will fix again with more tapping of the relay. I pick up
a new relay at Benz. They sold me a new and improved version of relay
with a promise that it would work in my car despite the fact that it
has 8 pins instead of just 4. No it did not fix my problem. Tapping
on it doesn't make it work either. When I replace the original I get
intermittent success. It will work then not.???? I am trying to see
if there is some other thing that could cause the problem I am having
but seem to be stuck on "it's the over volt relay".
My first question is can someone who knows verify that a part #
201.540.37.45 can be used in place of a part # 126.540.47.45 This part
is either bad or is wrong or I have something else wrong with my car
that is screwing up both of these relays in different ways.
Second question is what influences this relay to provide power on not
to provide power. The way I see it you give it 12 volts and you get 12
volts out. You give other then 12 volts and you get no volt out.