diff --git a/firmware/controllers/sensors/impl/AemXSeriesLambda.cpp b/firmware/controllers/sensors/impl/AemXSeriesLambda.cpp
index 929be7a794..e580e14b9e 100644
--- a/firmware/controllers/sensors/impl/AemXSeriesLambda.cpp
+++ b/firmware/controllers/sensors/impl/AemXSeriesLambda.cpp
@@ -11,6 +11,9 @@ static constexpr uint32_t rusefi_base = WB_DATA_BASE_ADDR;
 #define HACK_SILENT_VALUE 1
 // todo: suggest values 1 and 2 into the official WB source fault enum?
 #define HACK_CRANKING_VALUE 2
+// todo: static_cast<uint8_t>(Fault::LegacyProtocol);
+#define HACK_VALID_AEM 7
+#define HACK_INVALID_AEM 8
 
 AemXSeriesWideband::AemXSeriesWideband(uint8_t sensorIndex, SensorType type)
 	: CanSensorBase(
@@ -57,8 +60,8 @@ void AemXSeriesWideband::decodeFrame(const CANRxFrame& frame, efitick_t nowNt) {
 	// accept frame has already guaranteed that this message belongs to us
 	// We just have to check if it's AEM or rusEFI
 	if (id < rusefi_base) {
-		decodeAemXSeries(frame, nowNt);
-		faultCode = 7;//static_cast<uint8_t>(Fault::LegacyProtocol);
+		bool isValidAemX = decodeAemXSeries(frame, nowNt);
+		faultCode = isValidAemX ? HACK_VALID_AEM : HACK_INVALID_AEM;
 	} else {
 		// rusEFI custom format
 		if ((id & 0x1) != 0) {
@@ -71,7 +74,10 @@ void AemXSeriesWideband::decodeFrame(const CANRxFrame& frame, efitick_t nowNt) {
 	}
 }
 
-void AemXSeriesWideband::decodeAemXSeries(const CANRxFrame& frame, efitick_t nowNt) {
+/**
+ * @return true if valid, false if invalid
+ */
+bool AemXSeriesWideband::decodeAemXSeries(const CANRxFrame& frame, efitick_t nowNt) {
 	// reports in 0.0001 lambda per LSB
 	uint16_t lambdaInt = SWAP_UINT16(frame.data16[0]);
 	float lambdaFloat = 0.0001f * lambdaInt;
@@ -80,17 +86,18 @@ void AemXSeriesWideband::decodeAemXSeries(const CANRxFrame& frame, efitick_t now
 	bool sensorFault = frame.data8[7] & 0x40;
 	if (sensorFault) {
 		invalidate();
-		return;
+		return false;
 	}
 
 	// bit 7 indicates valid
 	bool valid = frame.data8[6] & 0x80;
 	if (!valid) {
 		invalidate();
-		return;
+		return false;
 	}
 
 	setValidValue(lambdaFloat, nowNt);
+	return true;
 }
 
 void AemXSeriesWideband::decodeRusefiStandard(const CANRxFrame& frame, efitick_t nowNt) {
diff --git a/firmware/controllers/sensors/impl/AemXSeriesLambda.h b/firmware/controllers/sensors/impl/AemXSeriesLambda.h
index 0ae974f0cd..e4f2127109 100644
--- a/firmware/controllers/sensors/impl/AemXSeriesLambda.h
+++ b/firmware/controllers/sensors/impl/AemXSeriesLambda.h
@@ -17,7 +17,7 @@ protected:
 	void decodeFrame(const CANRxFrame& frame, efitick_t nowNt) override;
 
 	// Decode an actual AEM controller, or a rusEFI controller sending AEM format
-	void decodeAemXSeries(const CANRxFrame& frame, efitick_t nowNt);
+	bool decodeAemXSeries(const CANRxFrame& frame, efitick_t nowNt);
 
 	// Decode rusEFI custom format
 	void decodeRusefiStandard(const CANRxFrame& frame, efitick_t nowNt);
diff --git a/firmware/tunerstudio/tunerstudio.template.ini b/firmware/tunerstudio/tunerstudio.template.ini
index 8740d7ea7e..183a26eee7 100644
--- a/firmware/tunerstudio/tunerstudio.template.ini
+++ b/firmware/tunerstudio/tunerstudio.template.ini
@@ -3574,13 +3574,14 @@ cmd_set_engine_type_default					= "@@TS_IO_TEST_COMMAND_char@@@@ts_command_e_TS_
 	dialog = egoSettings_IO2,	"O2 Sensor 2 I/O"
 		field = "Input channel",						afr_hwChannel2
 
-	indicatorPanel = uegoCan0Indicators, 1, { enableAemXSeries == 1 }
+	indicatorPanel = uegoCan0Indicators, 1, { enableAemXSeries == 1 && (faultCode0 == 7 || faultCode0 == 8) }
 		indicator = { faultCode0 == 7 }, "RusEFI WBO", "AEM Gauge", green, black, yellow, black
+		indicator = { faultCode0 == 8 }, "AEM OK", "AEM ERROR", green, black, yellow, black
 
-	indicatorPanel = uegoCan1Indicators, 1, { enableAemXSeries == 1 }
+	indicatorPanel = uegoCan1Indicators, 1, { enableAemXSeries == 1 && (faultCode0 == 7 || faultCode0 == 8) }
 		indicator = { faultCode1 == 7 }, "RusEFI WBO", "AEM Gauge", green, black, yellow, black
 
-	indicatorPanel = uegoCan0IndicatorsExt, 1, { enableAemXSeries == 1 && faultCode0 != 7 }
+	indicatorPanel = uegoCan0IndicatorsExt, 1, { enableAemXSeries == 1 && faultCode0 != 7 && faultCode0 != 8 }
 		indicator = { faultCode0 == 0 || faultCode0 == 7 }, "Failed", "Ready/Ok", red, black, green, black
 		indicator = { faultCode0 == 2 }, "Heating allowed", "Heating prohibited", green, black, yellow, black
 		indicator = { faultCode0 == 1 }, "Communication ok", "Timeout reading", green, black, red, black
@@ -3589,7 +3590,7 @@ cmd_set_engine_type_default					= "@@TS_IO_TEST_COMMAND_char@@@@ts_command_e_TS_
 		indicator = { faultCode0 == 5 }, "No underheat", "Underheat", green, black, red, black
 		indicator = { faultCode0 == 6 }, "Heater supply ok", "No heater supply", green, black, yellow, black
 
-	indicatorPanel = uegoCan1IndicatorsExt, 1, { enableAemXSeries == 1 && faultCode1 != 7 }
+	indicatorPanel = uegoCan1IndicatorsExt, 1, { enableAemXSeries == 1 && faultCode1 != 7 && faultCode0 != 8 }
 		indicator = { faultCode1 == 0 || faultCode1 == 7 }, "Failed", "Ready/Ok", red, black, green, black
 		indicator = { faultCode1 == 2 }, "Heating allowed", "Heating prohibited", green, black, yellow, black
 		indicator = { faultCode1 == 1 }, "Communication ok", "Timeout reading", green, black, red, black