How can I setup a 2862Ln to switch to LTE when data stops flowing on WAN2?

It's easy enough to setup a failover so LTE kicks in when WAN2's Ethernet is disconnected. However in my case WAN2 stays connected but stops transmitting data (it's a satellite link and drops occassionally). I'd like a configuration where LTE is used until data connectivity returns on WAN2.

I've tried using load balance/route policy but can't get it to work or to switch back to WAN2 (I also think there is a DNS problem when it switches to LTE).

It seems something that would be a common requirement but I can't find anyone who has documented how to get it working.

Any ideas please?

So doesn't setting "WAN Connection Detection" to "Ping Detect" do the trick?

THANKS!
I'm not sure how I missed that setting. I had it in "ARP Detect" mode (which does not show the controls for entering a ping address). It looks like it's working now. I'll test a little more tomorrow. Many thanks again! Andrew