diff --git a/Ccs/ccs_function_lib.py b/Ccs/ccs_function_lib.py
index c93967bd572e551fcf7c18aee1cbb1b60a95ad08..ae0e2f9c1d846760058c672629a953791cbc909f 100644
--- a/Ccs/ccs_function_lib.py
+++ b/Ccs/ccs_function_lib.py
@@ -1989,10 +1989,18 @@ def tc_param_alias(param, val, no_check=False):
         else:
             # subtract offset from PID to be compatible with IASW (CHEOPS only)
             if param in ['DPP70004', 'DPP70043']:
-                val -= pid_offset
+                try:
+                    val -= pid_offset
+                except TypeError:
+                    val = DP_ITEMS_TO_IDS[val]
+                    val -= pid_offset
     else:
         if param in ['DPP70004', 'DPP70043']:
-            val -= pid_offset
+            try:
+                val -= pid_offset
+            except TypeError:
+                val = DP_ITEMS_TO_IDS[val]
+                val -= pid_offset
 
     if paf is not None: