STM32 HAL uno de los cuatro pines de PWM permanece alto

Quiero usar los pines A15, B3, B4 y B5 para PWM usando Timer2 y Timer3 en STM32F103C8T6. Usando un código basado en uno generado por CubeMX, tengo los pines A15, B3, B4 funcionando correctamente, pero B5 está constantemente atascado en lo alto. Probé utilizando GPIO normal, y los cuatro pines pueden cambiar sus estados (por lo que no es un problema fuera del microcontrolador)

int main(void)
{
    HAL_Init();
    SystemClock_Config();

    MX_GPIO_Init();
    MX_DMA_Init();
    MX_USART1_UART_Init();
    MX_I2C1_Init();
    MX_ADC1_Init();
    MX_TIM2_Init();
    MX_TIM3_Init();
    MX_TIM4_Init();

    HAL_ADC_Start(&hadc1);
    HAL_ADCEx_Calibration_Start(&hadc1);
    HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_1); //A15
    HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_2); //B3
    HAL_TIM_PWM_Start(&htim3, TIM_CHANNEL_1); //B4
    HAL_TIM_PWM_Start(&htim3, TIM_CHANNEL_2); //B5

    while (1)
    {
        TIM2->CCR1 = 50;
        TIM2->CCR2 = 50;
        TIM3->CCR1 = 50;
        TIM3->CCR2 = 50;
    }   
}

void SystemClock_Config(void)
{

    RCC_OscInitTypeDef RCC_OscInitStruct;
    RCC_ClkInitTypeDef RCC_ClkInitStruct;
    RCC_PeriphCLKInitTypeDef PeriphClkInit;

    /**Initializes the CPU, AHB and APB busses clocks
     */
    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
    RCC_OscInitStruct.HSEState = RCC_HSE_ON;
    RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
    RCC_OscInitStruct.HSIState = RCC_HSI_ON;
    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
    RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    /**Initializes the CPU, AHB and APB busses clocks
     */
    RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
            |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_ADC;
    PeriphClkInit.AdcClockSelection = RCC_ADCPCLK2_DIV6;
    if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    /**Configure the Systick interrupt time
     */
    HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);

    /**Configure the Systick
     */
    HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);

    /* SysTick_IRQn interrupt configuration */
    HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}

static void MX_TIM2_Init(void)
{

    TIM_ClockConfigTypeDef sClockSourceConfig;
    TIM_MasterConfigTypeDef sMasterConfig;
    TIM_OC_InitTypeDef sConfigOC;

    htim2.Instance = TIM2;
    htim2.Init.Prescaler = 719;
    htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
    htim2.Init.Period = 99;
    htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
    htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
    if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
    if (HAL_TIM_ConfigClockSource(&htim2, &sClockSourceConfig) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    if (HAL_TIM_PWM_Init(&htim2) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
    sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
    if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = 0;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    HAL_TIM_MspPostInit(&htim2);

}

/* TIM3 init function */
static void MX_TIM3_Init(void)
{

    TIM_ClockConfigTypeDef sClockSourceConfig;
    TIM_MasterConfigTypeDef sMasterConfig;
    TIM_OC_InitTypeDef sConfigOC;

    htim3.Instance = TIM3;
    htim3.Init.Prescaler = 719;
    htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
    htim3.Init.Period = 99;
    htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
    htim3.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
    if (HAL_TIM_Base_Init(&htim3) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
    if (HAL_TIM_ConfigClockSource(&htim3, &sClockSourceConfig) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    if (HAL_TIM_PWM_Init(&htim3) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
    sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
    if (HAL_TIMEx_MasterConfigSynchronization(&htim3, &sMasterConfig) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = 0;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    if (HAL_TIM_PWM_ConfigChannel(&htim3, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    if (HAL_TIM_PWM_ConfigChannel(&htim3, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
    {
        _Error_Handler(__FILE__, __LINE__);
    }

    HAL_TIM_MspPostInit(&htim3);

}