diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index 52b4906..dc94b74 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -165,8 +165,7 @@
 	SI2quaterRestOctetsList si2quater optional,
 	SystemInformationType3 si3 optional,
 	SystemInformationType4 si4 optional,
-	/* TODO: replace with proper decoding of SI13, implement SI13 in GSM_SystemInformation.ttcn */
-	octetstring si13 optional,
+	SystemInformationType13 si13 optional,
 	SystemInformationType5 si5 optional,
 	SystemInformationType5bis si5bis optional,
 	SystemInformationType5ter si5ter optional,
@@ -371,7 +370,44 @@
 		s := omit
 	    }
 	},
-	si13 := '9000185A6FC9E08410AB2B2B2B2B2B2B2B2B2B2B'O,
+	si13 := {
+		rest_octets := {
+			presence := '1'B,
+			bcch_change_mark := ?,
+			si_change_field := '0000'B,
+			presence2 := '0'B,
+			si13_change_mark := omit,
+			gprs_ma := omit,
+			zero := '0'B, /* PBCCH not present in cell */
+			rac := 0,
+			spgc_ccch_sup := '0'B,
+			priority_access_thr := '110'B,
+			network_control_order := '00'B,
+			gprs_cell_opts := {
+				nmo := '01'B,
+				t3168 := '011'B,
+				t3192 := '010'B,
+				drx_timer_max := '011'B,
+				access_burst_type := '0'B,
+				control_ack_type := '1'B,
+				bs_cv_max := 15,
+				pan_presence := '1'B,
+				pan_dec  := 1,
+				pan_inc  := 1,
+				pan_max  := '111'B,
+				ext_info_presence := ?,
+				ext_info_length := *,
+				ext_info := *
+			},
+			gprs_pwr_ctrl_params := {
+				alpha := 0,
+				t_avg_w := '10000'B,
+				t_avg_t := '10000'B,
+				pc_meas_chan := '0'B,
+				n_avg_i := '1000'B
+			}
+		}
+	},
 	si5 := {
 	    bcch_freq_list := '10000000000000000000000000000000'O
 	},
@@ -480,7 +516,7 @@
 			if (not isbound(data)) {
 				si.si13 := omit;
 			} else {
-				si.si13 := dec_SystemInformation(data).payload.other;
+				si.si13 := dec_SystemInformation(data).payload.si13;
 			}
 		} else {
 			handled := false;