Because the connection is encrypted to the client, you'll either need to use a browser-based plugin (Live HTTP Headers, IEWatch, HTTPWatch), or configure a proxy (Fiddler) or wire capture (Wireshark) to be able to intercept and decrypt the SSL.
However you do it, you need to be able to inspect the underlying HTTP data to see what the client is receiving and what it's asking for.
Wireshark's SSL decryption instructions are here: http://wiki.wireshark.org/SSL
You can also use SSLDUMP in the BIG-IP shell to decrypt and inspect the data:
ssldump -k -i 0.0 -AdnN
where:
-k is the private used in the client SSL profile
-i is the interface (0.0 is all interfaces)
-A means get everything
-d means decrypt the traffic
-n means don't try to resolve
-N means parse ASN.1 data
is a required TCPDUMP-style filter
ex. ssldump -k
You need to be in front of SSL negotiation, so clear the SSL state in your browser between tests.
** You could also try turning off SSL on the client side just long enough to see if (a it works without SSL or b) what the client is sending/receiving.