Many thanks info. It looks very possible you are right. Can I come back to you when we have been able to try out your suggestions.
Once again thank you.
Many thanks Greg,
The car is running and seems ok, but as stated ealier it has been an intermittent fault and so we cannot say if the fault has been rectified. The car was running prior to your reply re the relays. We fitted 1 of the relays but could not locate where the other one went. We even spoke Merc main dealer and tried with their suggestions but we still could not find where to put the 2nd relay. The car is running but we wait and see.