Harmony Boxer Petrol 1996. Fridge RED light?

Recently the Red light on the Fridge has stopped working [and so has the fridge] when travelling on the road.
My Manual tells me to CHECK the fuse then RELAY 'at rear of panel' not operating.-Test relay

1. All fuses in the ZIG panel above the rear door are FINE - so

2. I must check the Relay . Please does anyone know where I find the relay and approx size or what it looks like.
I ask this BECAUSE behind the the Zig panel there are two wire looms and a lot of empty space BUT NO RELAY.
Any guidance will be appreciated. Thank you

Two fuses hang above engine battery. One is for fridge, the other for split charge. Common corrosion problem of the fuse holders.