synchronising immobiliser

1996 300E diesel. I cannot synchronise the immobiliser correctly using the key fob and rear mirror receiver. I tried pressing the button twice then
turning the ignition key, this should sync the immobiliser, but I keep getting red and green lights flashing together on the rear mirror receiver, the engine turns over but no ignition. What now?
Charlie Brown London
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
You're supposed to hold the button down for 10 seconds, then turn the ignition on.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.