diff --git a/healthd/Android.mk b/healthd/Android.mk
index d725f73..5f10f1e 100644
--- a/healthd/Android.mk
+++ b/healthd/Android.mk
@@ -96,7 +96,7 @@
 LOCAL_CFLAGS += -DBOARD_PERIODIC_CHORES_INTERVAL_SLOW=$(BOARD_PERIODIC_CHORES_INTERVAL_SLOW)
 endif
 
-LOCAL_STATIC_LIBRARIES := \
+CHARGER_STATIC_LIBRARIES := \
     android.hardware.health@2.0-impl \
     android.hardware.health@2.0 \
     android.hardware.health@1.0 \
@@ -114,6 +114,8 @@
     libm \
     libc \
 
+LOCAL_STATIC_LIBRARIES := $(CHARGER_STATIC_LIBRARIES)
+
 ifneq ($(strip $(LOCAL_CHARGER_NO_UI)),true)
 LOCAL_STATIC_LIBRARIES += \
     libminui \
@@ -134,6 +136,21 @@
 
 include $(BUILD_EXECUTABLE)
 
+include $(CLEAR_VARS)
+LOCAL_MODULE := charger_test
+LOCAL_MODULE_TAGS := optional
+LOCAL_FORCE_STATIC_EXECUTABLE := true
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
+LOCAL_CFLAGS := -Wall -Werror -DCHARGER_TEST -DCHARGER_NO_UI
+LOCAL_STATIC_LIBRARIES := $(CHARGER_STATIC_LIBRARIES)
+LOCAL_SRC_FILES := \
+    charger.cpp \
+    charger_test.cpp \
+
+include $(BUILD_EXECUTABLE)
+
+CHARGER_STATIC_LIBRARIES :=
+
 ifneq ($(strip $(LOCAL_CHARGER_NO_UI)),true)
 define _add-charger-image
 include $$(CLEAR_VARS)
diff --git a/healthd/charger.cpp b/healthd/charger.cpp
index ede14f2..43e7fd5 100644
--- a/healthd/charger.cpp
+++ b/healthd/charger.cpp
@@ -79,7 +79,7 @@
     struct android::BatteryProperties* /*props*/) {
 }
 
-int main(int argc, char **argv) {
+int healthd_charger_main(int argc, char** argv) {
     int ch;
 
     healthd_mode_ops = &charger_ops;
@@ -103,3 +103,9 @@
 
     return healthd_main();
 }
+
+#ifndef CHARGER_TEST
+int main(int argc, char** argv) {
+    return healthd_charger_main(argc, argv);
+}
+#endif
diff --git a/healthd/charger_test.cpp b/healthd/charger_test.cpp
new file mode 100644
index 0000000..acc0f5b
--- /dev/null
+++ b/healthd/charger_test.cpp
@@ -0,0 +1,174 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "charger_test"
+#include <android/log.h>
+
+#include <chrono>
+#include <condition_variable>
+#include <fstream>
+#include <iostream>
+#include <mutex>
+#include <streambuf>
+#include <string>
+#include <thread>
+#include <vector>
+
+#include <healthd/healthd.h>
+
+#define LOG_THIS(fmt, ...)     \
+    ALOGE(fmt, ##__VA_ARGS__); \
+    printf(fmt "\n", ##__VA_ARGS__);
+
+template <typename T>
+class Atomic {
+  public:
+    Atomic(T&& init) : mValue(std::move(init)) {}
+    void set(T&& newVal) {
+        {
+            std::lock_guard<std::mutex> lock(mMutex);
+            mValue = std::move(newVal);
+        }
+        mChanged.notify_all();
+    }
+    bool waitFor(long ms, const T& expectVal) {
+        std::unique_lock<std::mutex> lock(mMutex);
+        return mChanged.wait_for(lock, std::chrono::milliseconds(ms),
+                                 [this, &expectVal] { return mValue == expectVal; });
+    }
+  private:
+    std::mutex mMutex;
+    std::condition_variable mChanged;
+    T mValue;
+};
+
+Atomic<bool>& getUpdateNotifier() {
+    static Atomic<bool> val(false);
+    return val;
+}
+
+int energyCounter(int64_t* counter) {
+    *counter = 0xEC12345;
+    return 0;
+}
+
+const char* createFile(const char* path, const char* content) {
+    std::ofstream stream(path);
+    if (!stream.is_open()) {
+        LOG_THIS("Cannot create file %s", path);
+        return NULL;
+    }
+    stream << content << std::endl;
+    stream.close();
+    return path;
+}
+
+std::string openToString(const char* path) {
+    std::ifstream stream(path);
+    if (!stream.is_open()) {
+        LOG_THIS("Cannot open file %s", path);
+        return "";
+    }
+    return std::string(std::istreambuf_iterator<char>(stream), std::istreambuf_iterator<char>());
+}
+
+int expectContains(const std::string& content, const std::vector<std::string>& fields) {
+    int status = 0;
+    for (const auto& field : fields) {
+        auto pos = content.find(field);
+        if (pos == std::string::npos) {
+            LOG_THIS("Cannot find substr '%s'", field.c_str());
+            status = 1;
+        }
+    }
+    return status;
+}
+
+void healthd_board_init(struct healthd_config* config) {
+    config->periodic_chores_interval_fast = 60;
+    config->periodic_chores_interval_slow = 600;
+
+    config->batteryStatusPath = createFile("/data/local/tmp/batteryStatus", "Not charging");
+    config->batteryHealthPath = createFile("/data/local/tmp/batteryHealth", "Unspecified failure");
+    config->batteryPresentPath = createFile("/data/local/tmp/batteryPresent", "1");
+    config->batteryCapacityPath = createFile("/data/local/tmp/batteryCapacity", "47");
+    config->batteryVoltagePath = createFile("/data/local/tmp/batteryVoltage", "45000");
+    config->batteryTemperaturePath = createFile("/data/local/tmp/batteryTemperature", "987");
+    config->batteryTechnologyPath = createFile("/data/local/tmp/batteryTechnology", "NiCd");
+    config->batteryCurrentNowPath = createFile("/data/local/tmp/batteryCurrentNow", "99000");
+    config->batteryCurrentAvgPath = createFile("/data/local/tmp/batteryCurrentAvg", "98000");
+    config->batteryChargeCounterPath = createFile("/data/local/tmp/batteryChargeCounter", "600");
+    config->batteryFullChargePath = createFile("/data/local/tmp/batteryFullCharge", "3515547");
+    config->batteryCycleCountPath = createFile("/data/local/tmp/batteryCycleCount", "77");
+
+    config->energyCounter = energyCounter;
+    config->boot_min_cap = 50;
+    config->screen_on = NULL;
+}
+
+int healthd_board_battery_update(struct android::BatteryProperties*) {
+    getUpdateNotifier().set(true /* updated */);
+
+    // return 0 to log periodic polled battery status to kernel log
+    return 0;
+}
+
+extern int healthd_charger_main(int argc, char** argv);
+
+int main(int argc, char** argv) {
+    const char* dumpFile = "/data/local/tmp/dump.txt";
+
+    std::thread bgThread([=] {
+        healthd_charger_main(argc, argv);
+    });
+
+    // wait for healthd_init to finish
+    if (!getUpdateNotifier().waitFor(1000 /* wait ms */, true /* updated */)) {
+        LOG_THIS("Time out.");
+        exit(1);
+    }
+
+    int fd = creat(dumpFile, S_IRUSR | S_IWUSR);
+    if (fd < 0) {
+        exit(errno);
+    }
+    healthd_dump_battery_state(fd);
+    close(fd);
+
+    std::string content = openToString(dumpFile);
+    int status = expectContains(content, {
+        "status: 4",
+        "health: 6",
+        "present: 1",
+        "level: 47",
+        "voltage: 45",
+        "temp: 987",
+        "current now: 99000",
+        "current avg: 98000",
+        "charge counter: 600",
+        "current now: 99",
+        "cycle count: 77",
+        "Full charge: 3515547"
+    });
+
+    if (status == 0) {
+        LOG_THIS("Test success.");
+    } else {
+        LOG_THIS("Actual dump:\n%s", content.c_str());
+    }
+
+    exit(status);  // force bgThread to exit
+}