diff --git a/firmware/config/boards/hellen/alphax-2chan/trigger_scope_config.h b/firmware/config/boards/hellen/alphax-2chan/trigger_scope_config.h
index e009829c61..e43852335e 100644
--- a/firmware/config/boards/hellen/alphax-2chan/trigger_scope_config.h
+++ b/firmware/config/boards/hellen/alphax-2chan/trigger_scope_config.h
@@ -8,3 +8,5 @@
 #define TRIGGER_SCOPE_ADC_CH1 H144_ADC_IN_RES3
 
 #define TRIGGER_SCOPE_HAS_CH2 false
+// todo: fix https://github.com/rusefi/rusefi/issues/4909
+#define TRIGGER_SCOPE_ADC_CH2 H144_ADC_IN_RES2