diff --git a/.github/workflows/iwyu.yml b/.github/workflows/iwyu.yml
index 9ed9323f27e..0ebcb14bcaa 100644
--- a/.github/workflows/iwyu.yml
+++ b/.github/workflows/iwyu.yml
@@ -55,7 +55,7 @@ jobs:
           -DACTS_BUILD_EXAMPLES_EDM4HEP=ON
 
       - name: Run IWYU
-        run: python3 iwyu-install/bin/iwyu_tool.py -p acts-build/ -j2 -- -Xiwyu --mapping_file=acts/CI/iwyu/mapping.imp | tee iwyu-output.txt
+        run: python3 iwyu-install/bin/iwyu_tool.py -p acts-build/ -j2 -- -Xiwyu --mapping_file=$(pwd)/acts/CI/iwyu/mapping.imp | tee iwyu-output.txt
       - name: Filter IWYU output
         run: python3 acts/CI/iwyu/filter.py acts/CI/iwyu/filter.yaml iwyu-output.txt iwyu-filtered.txt
       - name: Apply IWYU