diff --git a/firmware/config/engines/custom_engine.cpp b/firmware/config/engines/custom_engine.cpp
index f59b2a72e8..10848e54ba 100644
--- a/firmware/config/engines/custom_engine.cpp
+++ b/firmware/config/engines/custom_engine.cpp
@@ -62,6 +62,8 @@ void setCustomEngineConfiguration(engine_configuration_s *engineConfiguration) {
 	 * We want to initialize all outputs for test
 	 */
 	engineConfiguration->cylindersCount = 10;
+
+	engineConfiguration->displayMode = DM_NONE;
 #else
 	boardConfiguration->injectionPins[4] = GPIO_UNASSIGNED;
 	boardConfiguration->injectionPins[5] = GPIO_UNASSIGNED;
diff --git a/firmware/config/stm32f4ems/efifeatures.h b/firmware/config/stm32f4ems/efifeatures.h
index 2a52d04a4a..7d513df778 100644
--- a/firmware/config/stm32f4ems/efifeatures.h
+++ b/firmware/config/stm32f4ems/efifeatures.h
@@ -14,6 +14,8 @@
 
 #define EFI_FSIO TRUE
 
+#define EFI_PWM_TESTER FALSE
+
 #define EFI_USE_CCM TRUE
 
 #ifndef EFI_ENABLE_ASSERTS
diff --git a/firmware/controllers/PwmTester.cpp b/firmware/controllers/PwmTester.cpp
index 0b09907c14..1ebb018e89 100644
--- a/firmware/controllers/PwmTester.cpp
+++ b/firmware/controllers/PwmTester.cpp
@@ -13,37 +13,76 @@
 #include "PwmTester.h"
 #include "EfiWave.h"
 #include "pwm_generator_logic.h"
-#include "engine_configuration.h"
+#include "engine.h"
 #include "pwm_generator.h"
 
-static Logging logger;
+static LoggingWithStorage logger;
 
 static SimplePwm pwmTest[5];
 
-extern board_configuration_s *boardConfiguration;
-
 extern OutputPin warningPin;
-extern OutputPin outputs[IO_PIN_COUNT];
+extern engine_pins_s enginePins;
+
+EXTERN_ENGINE;
 
 static void startPwmTest(int freq) {
 	scheduleMsg(&logger, "running pwm test @%d", freq);
 
-	// PD13, GPIO_UNASSIGNED because pin is initialized elsewhere already
+	engine->isRunningPwmTest = true;
+
+	// PD13 pin is initialized elsewhere already
 	startSimplePwm(&pwmTest[0], "tester", &warningPin, 10, 0.5f, applyPinState);
+	/**
+	 * See custom_engine.cpp for pinout
+	 */
 	// currently this is PB9 by default - see boardConfiguration->injectionPins
-	startSimplePwm(&pwmTest[1], "tester", &outputs[(int)INJECTOR_1_OUTPUT], freq / 1.3333333333, 0.5f, applyPinState);
+	startSimplePwm(&pwmTest[1], "tester", &enginePins.injectors[0], freq / 1.3333333333, 0.5f, applyPinState);
+	// currently this is PE2 by default
+	startSimplePwm(&pwmTest[2], "tester", &enginePins.injectors[1], freq / 1000, 0.5f, applyPinState);
 	// currently this is PB8 by default
-	startSimplePwm(&pwmTest[2], "tester", &outputs[(int)INJECTOR_2_OUTPUT], freq / 1000, 0.5f, applyPinState);
-	// currently this is PE3 by default
-	startSimplePwm(&pwmTest[3], "tester", &outputs[(int)INJECTOR_3_OUTPUT], freq, 0.5, applyPinState);
-	// currently this is PE5 by default
-	startSimplePwm(&pwmTest[4], "tester", &outputs[(int)INJECTOR_4_OUTPUT], freq / 33.33333333333, 0.5, applyPinState);
+	startSimplePwm(&pwmTest[3], "tester", &enginePins.injectors[2], freq, 0.5, applyPinState);
+	// currently this is PB7 by default
+	startSimplePwm(&pwmTest[4], "tester", &enginePins.injectors[3], freq / 33.33333333333, 0.5, applyPinState);
+
+}
+
+static scheduling_s ioTest;
+
+static OutputSignal outSignals[4];
+
+static void testCallback(void *arg) {
+
+	/**
+	 * 0.1ms from now please squirt for 1.6ms
+	 */
+	scheduleOutput(&outSignals[0], 0.1, 1.6);
+	scheduleOutput(&outSignals[1], 0.1, 1.6);
+	scheduleOutput(&outSignals[2], 0.1, 1.6);
+	scheduleOutput(&outSignals[3], 0.1, 1.6);
+
+	/**
+	 * this would re-schedule another callback in 2ms from now
+	 */
+	scheduleTask("test", &ioTest, MS2US(2), testCallback, NULL);
 }
 
 void initPwmTester(void) {
 	initLogging(&logger, "pwm test");
 	addConsoleActionI("pwmtest", startPwmTest);
-// un-comment this to start pwm test on start up 	startPwmTest(1000);
+	startPwmTest(1000);
+
+	/**
+	 * injector channels #4-#8 are used for individual squirt test
+	 */
+	outSignals[0].output = &enginePins.injectors[4];
+	outSignals[1].output = &enginePins.injectors[5];
+	outSignals[2].output = &enginePins.injectors[6];
+	outSignals[3].output = &enginePins.injectors[7];
+
+	/**
+	 * this would schedule a callback in 2ms from now
+	 */
+	scheduleTask("test", &ioTest, MS2US(2), testCallback, NULL);
 }
 
 #endif
diff --git a/firmware/controllers/algo/engine.cpp b/firmware/controllers/algo/engine.cpp
index ae312249c5..b9c5354070 100644
--- a/firmware/controllers/algo/engine.cpp
+++ b/firmware/controllers/algo/engine.cpp
@@ -46,6 +46,7 @@ Engine::Engine() {
 	isCylinderCleanupMode = false;
 	engineCycleEventCount = 0;
 	stopEngineRequestTimeNt = 0;
+	isRunningPwmTest = false;
 }
 
 void Engine::precalc(engine_configuration_s *engineConfiguration) {
@@ -76,6 +77,8 @@ bool Engine::stopPins() {
 }
 
 void Engine::watchdog() {
+	if (isRunningPwmTest)
+		return;
 	if (!isSpinning) {
 		if (!isRunningBenchTest() && stopPins()) {
 			firmwareError("Some pins were turned off by 2nd pass watchdog");
diff --git a/firmware/controllers/algo/engine.h b/firmware/controllers/algo/engine.h
index 12e01aebe1..1c29f1f4f9 100644
--- a/firmware/controllers/algo/engine.h
+++ b/firmware/controllers/algo/engine.h
@@ -103,6 +103,8 @@ public:
 	bool_t clutchUpState;
 	bool_t clutchDownState;
 
+	bool_t isRunningPwmTest;
+
 	TriggerShape triggerShape;
 
 	float angleExtra[IGNITION_PIN_COUNT];
diff --git a/firmware/controllers/system/scheduler.h b/firmware/controllers/system/scheduler.h
index 4619b99db9..f886210937 100644
--- a/firmware/controllers/system/scheduler.h
+++ b/firmware/controllers/system/scheduler.h
@@ -24,16 +24,7 @@ struct scheduling_struct {
 	const char *name;
 };
 
-#ifdef __cplusplus
-extern "C"
-{
-#endif /* __cplusplus */
-
 void scheduleTask(const char *prefix, scheduling_s *scheduling, int delayUs, schfunc_t callback, void *param);
 void scheduleTask2(const char *prefix, scheduling_s *scheduling, uint64_t time, schfunc_t callback, void *param);
 
-#ifdef __cplusplus
-}
-#endif /* __cplusplus */
-
 #endif /* SCHEDULER_H_ */