diff --git a/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp b/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp
index 3c2a360..101d4f5 100644
--- a/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp
+++ b/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp
@@ -16,12 +16,14 @@
 #include <aidl/Gtest.h>
 #include <aidl/Vintf.h>
 #include <aidl/android/hardware/vibrator/BnVibratorCallback.h>
+#include <aidl/android/hardware/vibrator/IVibrationSession.h>
 #include <aidl/android/hardware/vibrator/IVibrator.h>
 #include <aidl/android/hardware/vibrator/IVibratorManager.h>
 
 #include <android/binder_manager.h>
 #include <android/binder_process.h>
 
+#include <algorithm>
 #include <cmath>
 #include <future>
 
@@ -32,10 +34,14 @@
 using aidl::android::hardware::vibrator::CompositePrimitive;
 using aidl::android::hardware::vibrator::Effect;
 using aidl::android::hardware::vibrator::EffectStrength;
+using aidl::android::hardware::vibrator::IVibrationSession;
 using aidl::android::hardware::vibrator::IVibrator;
 using aidl::android::hardware::vibrator::IVibratorManager;
+using aidl::android::hardware::vibrator::VibrationSessionConfig;
 using std::chrono::high_resolution_clock;
 
+using namespace ::std::chrono_literals;
+
 const std::vector<Effect> kEffects{ndk::enum_range<Effect>().begin(),
                                    ndk::enum_range<Effect>().end()};
 const std::vector<EffectStrength> kEffectStrengths{ndk::enum_range<EffectStrength>().begin(),
@@ -43,6 +49,11 @@
 const std::vector<CompositePrimitive> kPrimitives{ndk::enum_range<CompositePrimitive>().begin(),
                                                   ndk::enum_range<CompositePrimitive>().end()};
 
+// Timeout to wait for vibration callback completion.
+static constexpr std::chrono::milliseconds VIBRATION_CALLBACK_TIMEOUT = 100ms;
+
+static constexpr int32_t VIBRATION_SESSIONS_MIN_VERSION = 3;
+
 class CompletionCallback : public BnVibratorCallback {
   public:
     CompletionCallback(const std::function<void()>& callback) : mCallback(callback) {}
@@ -64,9 +75,29 @@
         ASSERT_NE(manager, nullptr);
         EXPECT_OK(manager->getCapabilities(&capabilities));
         EXPECT_OK(manager->getVibratorIds(&vibratorIds));
+        EXPECT_OK(manager->getInterfaceVersion(&version));
+    }
+
+    virtual void TearDown() override {
+        // Reset manager state between tests.
+        if (capabilities & IVibratorManager::CAP_SYNC) {
+            manager->cancelSynced();
+        }
+        if (capabilities & IVibratorManager::CAP_START_SESSIONS) {
+            manager->clearSessions();
+        }
+        // Reset all managed vibrators.
+        for (int32_t id : vibratorIds) {
+            std::shared_ptr<IVibrator> vibrator;
+            EXPECT_OK(manager->getVibrator(id, &vibrator));
+            ASSERT_NE(vibrator, nullptr);
+            EXPECT_OK(vibrator->off());
+        }
     }
 
     std::shared_ptr<IVibratorManager> manager;
+    std::shared_ptr<IVibrationSession> session;
+    int32_t version;
     int32_t capabilities;
     std::vector<int32_t> vibratorIds;
 };
@@ -109,7 +140,7 @@
     if (vibratorIds.empty()) return;
     if (!(capabilities & IVibratorManager::CAP_SYNC)) return;
     if (!(capabilities & IVibratorManager::CAP_PREPARE_ON)) {
-        uint32_t durationMs = 250;
+        int32_t durationMs = 250;
         EXPECT_OK(manager->prepareSynced(vibratorIds));
         std::shared_ptr<IVibrator> vibrator;
         for (int32_t id : vibratorIds) {
@@ -170,7 +201,7 @@
     std::future<void> completionFuture{completionPromise.get_future()};
     auto callback = ndk::SharedRefBase::make<CompletionCallback>(
             [&completionPromise] { completionPromise.set_value(); });
-    uint32_t durationMs = 250;
+    int32_t durationMs = 250;
     std::chrono::milliseconds timeout{durationMs * 2};
 
     EXPECT_OK(manager->prepareSynced(vibratorIds));
@@ -202,6 +233,435 @@
     }
 }
 
+TEST_P(VibratorAidl, VibrationSessionsSupported) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    int32_t durationMs = 250;
+    std::vector<std::promise<void>> vibrationPromises;
+    std::vector<std::future<void>> vibrationFutures;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        std::promise<void>& vibrationPromise = vibrationPromises.emplace_back();
+        vibrationFutures.push_back(vibrationPromise.get_future());
+        auto vibrationCallback = ndk::SharedRefBase::make<CompletionCallback>(
+                [&vibrationPromise] { vibrationPromise.set_value(); });
+        EXPECT_OK(vibrator->on(durationMs, vibrationCallback));
+    }
+
+    auto timeout = std::chrono::milliseconds(durationMs) + VIBRATION_CALLBACK_TIMEOUT;
+    for (std::future<void>& future : vibrationFutures) {
+        EXPECT_EQ(future.wait_for(timeout), std::future_status::ready);
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // Ending a session should not take long since the vibration was already completed
+    EXPECT_OK(session->close());
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+}
+
+TEST_P(VibratorAidl, VibrationSessionInterrupted) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    std::vector<std::promise<void>> vibrationPromises;
+    std::vector<std::future<void>> vibrationFutures;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        std::promise<void>& vibrationPromise = vibrationPromises.emplace_back();
+        vibrationFutures.push_back(vibrationPromise.get_future());
+        auto vibrationCallback = ndk::SharedRefBase::make<CompletionCallback>(
+                [&vibrationPromise] { vibrationPromise.set_value(); });
+
+        // Vibration longer than test timeout.
+        EXPECT_OK(vibrator->on(2000, vibrationCallback));
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // Interrupt vibrations and session.
+    EXPECT_OK(session->abort());
+
+    // Both callbacks triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+    for (std::future<void>& future : vibrationFutures) {
+        EXPECT_EQ(future.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+    }
+}
+
+TEST_P(VibratorAidl, VibrationSessionEndingInterrupted) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    std::vector<std::promise<void>> vibrationPromises;
+    std::vector<std::future<void>> vibrationFutures;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        std::promise<void>& vibrationPromise = vibrationPromises.emplace_back();
+        vibrationFutures.push_back(vibrationPromise.get_future());
+        auto vibrationCallback = ndk::SharedRefBase::make<CompletionCallback>(
+                [&vibrationPromise] { vibrationPromise.set_value(); });
+
+        // Vibration longer than test timeout.
+        EXPECT_OK(vibrator->on(2000, vibrationCallback));
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // End session, this might take a while
+    EXPECT_OK(session->close());
+
+    // Interrupt ending session.
+    EXPECT_OK(session->abort());
+
+    // Both callbacks triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+    for (std::future<void>& future : vibrationFutures) {
+        EXPECT_EQ(future.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+    }
+}
+
+TEST_P(VibratorAidl, VibrationSessionCleared) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    int32_t durationMs = 250;
+    std::vector<std::promise<void>> vibrationPromises;
+    std::vector<std::future<void>> vibrationFutures;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        std::promise<void>& vibrationPromise = vibrationPromises.emplace_back();
+        vibrationFutures.push_back(vibrationPromise.get_future());
+        auto vibrationCallback = ndk::SharedRefBase::make<CompletionCallback>(
+                [&vibrationPromise] { vibrationPromise.set_value(); });
+        EXPECT_OK(vibrator->on(durationMs, vibrationCallback));
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // Clearing sessions should abort ongoing session
+    EXPECT_OK(manager->clearSessions());
+
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+    for (std::future<void>& future : vibrationFutures) {
+        EXPECT_EQ(future.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+    }
+}
+
+TEST_P(VibratorAidl, VibrationSessionsClearedWithoutSession) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+
+    EXPECT_OK(manager->clearSessions());
+}
+
+TEST_P(VibratorAidl, VibrationSessionsWithSyncedVibrations) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (!(capabilities & IVibratorManager::CAP_SYNC)) return;
+    if (!(capabilities & IVibratorManager::CAP_PREPARE_ON)) return;
+    if (!(capabilities & IVibratorManager::CAP_TRIGGER_CALLBACK)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    EXPECT_OK(manager->prepareSynced(vibratorIds));
+
+    int32_t durationMs = 250;
+    std::vector<std::promise<void>> vibrationPromises;
+    std::vector<std::future<void>> vibrationFutures;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        std::promise<void>& vibrationPromise = vibrationPromises.emplace_back();
+        vibrationFutures.push_back(vibrationPromise.get_future());
+        auto vibrationCallback = ndk::SharedRefBase::make<CompletionCallback>(
+                [&vibrationPromise] { vibrationPromise.set_value(); });
+        EXPECT_OK(vibrator->on(durationMs, vibrationCallback));
+    }
+
+    std::promise<void> triggerPromise;
+    std::future<void> triggerFuture{triggerPromise.get_future()};
+    auto triggerCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&triggerPromise] { triggerPromise.set_value(); });
+
+    EXPECT_OK(manager->triggerSynced(triggerCallback));
+
+    auto timeout = std::chrono::milliseconds(durationMs) + VIBRATION_CALLBACK_TIMEOUT;
+    EXPECT_EQ(triggerFuture.wait_for(timeout), std::future_status::ready);
+    for (std::future<void>& future : vibrationFutures) {
+        EXPECT_EQ(future.wait_for(timeout), std::future_status::ready);
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // Ending a session should not take long since the vibration was already completed
+    EXPECT_OK(session->close());
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::ready);
+}
+
+TEST_P(VibratorAidl, VibrationSessionWithMultipleIndependentVibrations) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        EXPECT_OK(vibrator->on(100, nullptr));
+        EXPECT_OK(vibrator->on(200, nullptr));
+        EXPECT_OK(vibrator->on(300, nullptr));
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    EXPECT_OK(session->close());
+
+    int32_t maxDurationMs = 100 + 200 + 300;
+    auto timeout = std::chrono::milliseconds(maxDurationMs) + VIBRATION_CALLBACK_TIMEOUT;
+    EXPECT_EQ(sessionFuture.wait_for(timeout), std::future_status::ready);
+}
+
+TEST_P(VibratorAidl, VibrationSessionsIgnoresSecondSessionWhenFirstIsOngoing) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    std::shared_ptr<IVibrationSession> secondSession;
+    EXPECT_ILLEGAL_STATE(
+            manager->startSession(vibratorIds, sessionConfig, nullptr, &secondSession));
+    EXPECT_EQ(secondSession, nullptr);
+
+    // First session was not cancelled.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // First session still ongoing, we can still vibrate.
+    int32_t durationMs = 100;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+        EXPECT_OK(vibrator->on(durationMs, nullptr));
+    }
+
+    EXPECT_OK(session->close());
+
+    auto timeout = std::chrono::milliseconds(durationMs) + VIBRATION_CALLBACK_TIMEOUT;
+    EXPECT_EQ(sessionFuture.wait_for(timeout), std::future_status::ready);
+}
+
+TEST_P(VibratorAidl, VibrationSessionEndMultipleTimes) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    int32_t durationMs = 250;
+    std::vector<std::promise<void>> vibrationPromises;
+    std::vector<std::future<void>> vibrationFutures;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        std::promise<void>& vibrationPromise = vibrationPromises.emplace_back();
+        vibrationFutures.push_back(vibrationPromise.get_future());
+        auto vibrationCallback = ndk::SharedRefBase::make<CompletionCallback>(
+                [&vibrationPromise] { vibrationPromise.set_value(); });
+        EXPECT_OK(vibrator->on(durationMs, vibrationCallback));
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // End session, this might take a while
+    EXPECT_OK(session->close());
+
+    // End session again
+    EXPECT_OK(session->close());
+
+    // Both callbacks triggered within timeout.
+    auto timeout = std::chrono::milliseconds(durationMs) + VIBRATION_CALLBACK_TIMEOUT;
+    EXPECT_EQ(sessionFuture.wait_for(timeout), std::future_status::ready);
+    for (std::future<void>& future : vibrationFutures) {
+        EXPECT_EQ(future.wait_for(timeout), std::future_status::ready);
+    }
+}
+
+TEST_P(VibratorAidl, VibrationSessionDeletedAfterEnded) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    std::promise<void> sessionPromise;
+    std::future<void> sessionFuture{sessionPromise.get_future()};
+    auto sessionCallback = ndk::SharedRefBase::make<CompletionCallback>(
+            [&sessionPromise] { sessionPromise.set_value(); });
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_OK(manager->startSession(vibratorIds, sessionConfig, sessionCallback, &session));
+    ASSERT_NE(session, nullptr);
+
+    int32_t durationMs = 250;
+    std::vector<std::promise<void>> vibrationPromises;
+    std::vector<std::future<void>> vibrationFutures;
+    for (int32_t id : vibratorIds) {
+        std::shared_ptr<IVibrator> vibrator;
+        EXPECT_OK(manager->getVibrator(id, &vibrator));
+        ASSERT_NE(vibrator, nullptr);
+
+        std::promise<void>& vibrationPromise = vibrationPromises.emplace_back();
+        vibrationFutures.push_back(vibrationPromise.get_future());
+        auto vibrationCallback = ndk::SharedRefBase::make<CompletionCallback>(
+                [&vibrationPromise] { vibrationPromise.set_value(); });
+        EXPECT_OK(vibrator->on(durationMs, vibrationCallback));
+    }
+
+    // Session callback not triggered.
+    EXPECT_EQ(sessionFuture.wait_for(VIBRATION_CALLBACK_TIMEOUT), std::future_status::timeout);
+
+    // End session, this might take a while
+    EXPECT_OK(session->close());
+
+    session.reset();
+
+    // Both callbacks triggered within timeout, even after session was deleted.
+    auto timeout = std::chrono::milliseconds(durationMs) + VIBRATION_CALLBACK_TIMEOUT;
+    EXPECT_EQ(sessionFuture.wait_for(timeout), std::future_status::ready);
+    for (std::future<void>& future : vibrationFutures) {
+        EXPECT_EQ(future.wait_for(timeout), std::future_status::ready);
+    }
+}
+
+TEST_P(VibratorAidl, VibrationSessionWrongVibratorIdsFail) {
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+
+    auto maxIdIt = std::max_element(vibratorIds.begin(), vibratorIds.end());
+    int32_t wrongId = maxIdIt == vibratorIds.end() ? 0 : *maxIdIt + 1;
+
+    std::vector<int32_t> emptyIds;
+    std::vector<int32_t> wrongIds{wrongId};
+    VibrationSessionConfig sessionConfig;
+    EXPECT_ILLEGAL_ARGUMENT(manager->startSession(emptyIds, sessionConfig, nullptr, &session));
+    EXPECT_ILLEGAL_ARGUMENT(manager->startSession(wrongIds, sessionConfig, nullptr, &session));
+    EXPECT_EQ(session, nullptr);
+}
+
+TEST_P(VibratorAidl, VibrationSessionDuringPrepareSyncedFails) {
+    if (!(capabilities & IVibratorManager::CAP_SYNC)) return;
+    if (!(capabilities & IVibratorManager::CAP_START_SESSIONS)) return;
+    if (vibratorIds.empty()) return;
+
+    EXPECT_OK(manager->prepareSynced(vibratorIds));
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_ILLEGAL_STATE(manager->startSession(vibratorIds, sessionConfig, nullptr, &session));
+    EXPECT_EQ(session, nullptr);
+
+    EXPECT_OK(manager->cancelSynced());
+}
+
+TEST_P(VibratorAidl, VibrationSessionsUnsupported) {
+    if (version < VIBRATION_SESSIONS_MIN_VERSION) {
+        EXPECT_EQ(capabilities & IVibratorManager::CAP_START_SESSIONS, 0)
+                << "Vibrator manager version " << version
+                << " should not report start session capability";
+    }
+    if (capabilities & IVibratorManager::CAP_START_SESSIONS) return;
+
+    VibrationSessionConfig sessionConfig;
+    EXPECT_UNKNOWN_OR_UNSUPPORTED(
+            manager->startSession(vibratorIds, sessionConfig, nullptr, &session));
+    EXPECT_EQ(session, nullptr);
+    EXPECT_UNKNOWN_OR_UNSUPPORTED(manager->clearSessions());
+}
+
 std::vector<std::string> FindVibratorManagerNames() {
     std::vector<std::string> names;
     constexpr auto callback = [](const char* instance, void* context) {
@@ -219,7 +679,7 @@
 
 int main(int argc, char** argv) {
     ::testing::InitGoogleTest(&argc, argv);
-    ABinderProcess_setThreadPoolMaxThreadCount(1);
+    ABinderProcess_setThreadPoolMaxThreadCount(2);
     ABinderProcess_startThreadPool();
     return RUN_ALL_TESTS();
 }
diff --git a/vibrator/aidl/vts/test_utils.h b/vibrator/aidl/vts/test_utils.h
index aaf3211..e884bbd 100644
--- a/vibrator/aidl/vts/test_utils.h
+++ b/vibrator/aidl/vts/test_utils.h
@@ -57,4 +57,17 @@
 #error Macro EXPECT_ILLEGAL_ARGUMENT already defined unexpectedly
 #endif
 
+#if !defined(EXPECT_ILLEGAL_STATE)
+#define EXPECT_ILLEGAL_STATE(expression)                                  \
+    GTEST_AMBIGUOUS_ELSE_BLOCKER_                                         \
+    if (const ::ndk::ScopedAStatus&& _status = (expression);              \
+        _status.getExceptionCode() == EX_ILLEGAL_STATE)                   \
+        ;                                                                 \
+    else                                                                  \
+        ADD_FAILURE() << "Expected EX_ILLEGAL_STATE for: " << #expression \
+                      << "\n  Actual: " << _status
+#else
+#error Macro EXPECT_ILLEGAL_STATE already defined unexpectedly
+#endif
+
 #endif  // VIBRATOR_HAL_TEST_UTILS_H