Have I broken my merc?

[sshenton1975]

Hi All

I have a R129 SL500 (1996)

Tonight whilst changing the battery in the boot, I damaged the Green fuel pump relay. I broke the outer casing but cannot see any damage inside to the relay

Now when i reconnect the battery and put relay back in, the fuel pump is humming constantly without the ignition being on!

The car will not start either........

Any ideas? FOr your info, when the relay is removed, the fuel pump continues to hum....again with no ignition on...

I am hoping I have not broken the fuel pump? Do you think it is just the relay? Not sure why fuel pump would run without the relay in and no ignition?

Thanks for your help

Simon

[chazola]

Sounds like maybe a short somewhere if the fuel pump is constantly running with the battery reconnected... Have you checked to see if any of the pins/sockets where the relay sits were damaged when you broke the relay casing?

Btw, you'd probably be better off with this in the Mercedes forum, R129sl will know better than me as he actually has an SL...

[Ray Luxury-Yacht]

I had an R129 and got to know it very well with my spanners, as it wasn't the most reliable car - most of the systems broke at some point or another.

Anyway - that's one problem I didn't have - very strange that the pump runs WITHOUT the relay being in it's socket. The only reason I can think of is that, yes, you've damaged the relay, and power to the fuel pump is supplied constantly by default, and the relay turns it OFF?


But I got most of my help and answers from the website Benzworld - Google it, there are some awesome techs on there.

Let us know how you get on.