diff --git a/Detectors/ITSMFT/common/reconstruction/include/ITSMFTReconstruction/ChipMappingITS.h b/Detectors/ITSMFT/common/reconstruction/include/ITSMFTReconstruction/ChipMappingITS.h
index b8add5f8106c2..9ba894208d45d 100644
--- a/Detectors/ITSMFT/common/reconstruction/include/ITSMFTReconstruction/ChipMappingITS.h
+++ b/Detectors/ITSMFT/common/reconstruction/include/ITSMFTReconstruction/ChipMappingITS.h
@@ -199,7 +199,7 @@ class ChipMappingITS
   uint8_t cableHW2Pos(uint8_t ruType, uint8_t hwid) const { return mCableHW2Pos[ruType][hwid]; }
 
   ///< convert HW cable ID to SW ID for given RU type (see ChipOnRUInfo.cableSW explanation)
-  uint8_t cableHW2SW(uint8_t ruType, uint8_t hwid) const { return mCableHW2SW[ruType][hwid]; }
+  uint8_t cableHW2SW(uint8_t ruType, uint8_t hwid) const { return hwid < mCableHW2SW[ruType].size() ? mCableHW2SW[ruType][hwid] : 0xff; }
 
   ///< convert cable iterator ID to the position on the ActiveLanes word in the GBT.header for given RU type; MFT lanes position compatible
   uint8_t cablePos(uint8_t ruType, uint8_t id) const { return mCablePos[ruType][id]; }