Xm V6 S1 Relays, replaced relay now tacho us

[paulxmski]

Hi all,

During investigation of non start problem on my V6si S1I found one of the relays on the front of the ECU had a slight burn on one of it's legs and some associated melting of the relay box. I replaced this relay with one from my other V6 they appeared to have the same rating 25amps and they had the same diagram on the side.

When I connected the replacement relay the car started but there was some buzzing (sounded like slight arcing) so I stopped the engine and looked around the engine bay without seeing any apparent problem. When I went for a short drive I suddenly noticed that the tacho needle was right over to the right and I assume that I must have blown it.

The relay in question is the only one of the five which does not have a hanger on it to clip it on the ECU box. I would like to know what this relay does? If there are likely to be any other problems associated with leaving the relay insitu i.e will it blow any other components?

This post has been edited by paulxmski on January 06, 2006 11:01 pm

[paulxmski]

Hi all,

Decided to have a look at the tachometer since manual said only 2 torx screws need undoing to remove the shroud. Removed binnacle/shroud easily with careful manouvering then undid the 4 torx to remove the instrument cluster. Undid the four small screws at the base of the cluster and the plastic glass came forward this released the tachometer needle which flew back to zero. Replaced all the components and then looked again at the relays retrieved the old relay with the burnt leg and reconnected it. Restarted the car and it ran for a minute, then stopped and would not restart. Removed the relay and replaced with the `new' relay car started and continued running. The tachometer operated correctly. The reason for the problem can only be summised but may relate to the tachometer being operated by sensing the pulses from the coil. When the car broke down in Wales the RAC mech put a tester on the coil this may have set up a high signal condition in the tachometer which caused the needle to flip across?

Alls well that ends well