diff --git a/firmware/console/binary/tunerstudio_commands.cpp b/firmware/console/binary/tunerstudio_commands.cpp
index 74e6b110bb..358c453305 100644
--- a/firmware/console/binary/tunerstudio_commands.cpp
+++ b/firmware/console/binary/tunerstudio_commands.cpp
@@ -47,8 +47,9 @@ void TunerStudio::cmdOutputChannels(TsChannelBase* tsChannel, uint16_t offset, u
 
 	tsState.outputChannelsCommandCounter++;
 	updateTunerStudioState();
+	tsChannel->assertPacketSize(count, false);
 	// this method is invoked too often to print any debug information
-	tsChannel->writeCrcPacket(TS_RESPONSE_OK, reinterpret_cast<const uint8_t*>(&engine->outputChannels) + offset, count);
+	tsChannel->writeCrcPacketSmall(TS_RESPONSE_OK, reinterpret_cast<const uint8_t*>(&engine->outputChannels) + offset, count);
 }
 
 #endif // EFI_TUNER_STUDIO
diff --git a/firmware/console/binary/tunerstudio_io.cpp b/firmware/console/binary/tunerstudio_io.cpp
index 6977628705..3975a4f7a5 100644
--- a/firmware/console/binary/tunerstudio_io.cpp
+++ b/firmware/console/binary/tunerstudio_io.cpp
@@ -79,6 +79,14 @@ TsChannelBase::TsChannelBase(const char *name) {
 	this->name = name;
 }
 
+#define isBigPacket(size) ((size) > BLOCKING_FACTOR + 7)
+
+void TsChannelBase::assertPacketSize(size_t size, bool allowLongPackets) {
+	if (isBigPacket(size) && !allowLongPackets) {
+		firmwareError(OBD_PCM_Processor_Fault, "tried to send disallowed long packet of size %d", size);
+	}
+}
+
 /**
  * Adds size to the beginning of a packet and a crc32 at the end. Then send the packet.
  */
@@ -88,13 +96,9 @@ void TsChannelBase::writeCrcPacket(uint8_t responseCode, const uint8_t* buf, siz
 		size = 0;
 	}
 
-	bool isBigPacket = size > BLOCKING_FACTOR + 7;
+	assertPacketSize(size, allowLongPackets);
 
-	if (isBigPacket && !allowLongPackets) {
-		firmwareError(OBD_PCM_Processor_Fault, "tried to send disallowed long packet of size %d", size);
-	}
-
-	if (isBigPacket) {
+	if (isBigPacket(size)) {
 		// for larger packets we do not use a buffer for CRC calculation meaning data is now allowed to modify while pending
 		writeCrcPacketLarge(responseCode, buf, size);
 	} else {
diff --git a/firmware/console/binary/tunerstudio_io.h b/firmware/console/binary/tunerstudio_io.h
index ce8535b69c..01a5e64aa1 100644
--- a/firmware/console/binary/tunerstudio_io.h
+++ b/firmware/console/binary/tunerstudio_io.h
@@ -58,8 +58,10 @@ public:
 	char scratchBuffer[BLOCKING_FACTOR + 30];
 	const char *name;
 
-private:
+	void assertPacketSize(size_t size, bool allowLongPackets);
 	void writeCrcPacketSmall(uint8_t responseCode, const uint8_t* buf, size_t size);
+
+private:
 	void writeCrcPacketLarge(uint8_t responseCode, const uint8_t* buf, size_t size);
 };