diff --git a/pcu/PCUIF_RAW_Components.ttcn b/pcu/PCUIF_RAW_Components.ttcn
index 7feeca26e..465e3980e 100644
--- a/pcu/PCUIF_RAW_Components.ttcn
+++ b/pcu/PCUIF_RAW_Components.ttcn
@@ -148,11 +148,12 @@ runs on RAW_PCU_ClckGen_CT {
 		} else if (fn13 == 3 or fn13 == 7 or fn13 == 11) {
 			/* 4/4 bursts of a PDTCH block on both Uplink and Downlink */
 			CLCK.send(ts_RAW_PCU_CLCK_EV(TDMA_EV_PDTCH_BLOCK_END, fn));
-		} else if (fn104 == 90) {
-			/* 4/4 bursts of a PTCCH (Timing Advance Control) block on Downlink */
-			CLCK.send(ts_RAW_PCU_CLCK_EV(TDMA_EV_PTCCH_DL_BLOCK, fn));
 		} else if (fn52 == 12 or fn52 == 38) {
-			/* One Access Burst on PTCCH/U */
+			/* 4/4 bursts of a PTCCH (Timing Advance Control) block on Downlink */
+			if (fn104 == 90) {
+				CLCK.send(ts_RAW_PCU_CLCK_EV(TDMA_EV_PTCCH_DL_BLOCK, fn));
+			}
+			/* One Access Burst on PTCCH/U (goes 3 time-slots after PTCCH/D) */
 			CLCK.send(ts_RAW_PCU_CLCK_EV(TDMA_EV_PTCCH_UL_BURST, fn));
 		}