Mira a ver si los módulos que has cambiado corresponden a la compilación del Kernel del boot.img (3.0.8, 3.0.8+...)
Otra cosa.... dentro de system.img, en etc hay carpeta llamada permissions con archivos xml, que son los que dan permisos al hardware, mira si dentro hay un archivo llamado android.hardware.sensor.accelerometer.xml con la linea:
<permissions>
<feature name="android.hardware.sensor.accelerometer" />
</permissions>
Otro que se llama platform.xml, en su interior:
<permissions>
<feature name="android.hardware.location" />
<!-- feature name="android.hardware.location.network" -->
<!-- feature name="android.hardware.sensor.compass" -->
<feature name="android.hardware.sensor.accelerometer" />
<feature name="android.hardware.touchscreen" />
<feature name="android.hardware.touchscreen.multitouch" />
<feature name="android.hardware.touchscreen.multitouch.dist inct" />
<feature name="android.hardware.microphone" />
<feature name="android.hardware.screen.portrait" />
<feature name="android.hardware.screen.landscape" />
<!-- devices with GPS must include android.hardware.location.gps.xml -->
<!-- devices with a rear-facing camera must include one of these as appropriate:
android.hardware.camera.xml or
android.hardware.camera.autofocus.xml or
android.hardware.camera.autofocus-flash.xml -->
<!-- devices with a front facing camera must include
android.hardware.camera.front.xml -->
<!-- devices with WiFi must also include android.hardware.wifi.xml -->
<!-- devices with an ambient light sensor must also include
android.hardware.sensor.light.xml -->
<!-- devices with a proximity sensor must also include
android.hardware.sensor.proximity.xml -->
<!-- devices with a barometer must also include
android.hardware.sensor.barometer.xml -->
<!-- devices with a gyroscope must also include
android.hardware.sensor.gyroscope.xml -->
<!-- GSM phones must also include android.hardware.telephony.gsm.xml -->
<!-- CDMA phones must also include android.hardware.telephony.cdma.xml -->
</permissions>
Y otro tablet_core_hardware.xml, en su interior:
<permissions>
<!-- ================================================== ================ -->
<!-- ================================================== ================ -->
<!-- ================================================== ================ -->
<!-- The following tags are associating low-level group IDs with
permission names. By specifying such a mapping, you are saying
that any application process granted the given permission will
also be running with the given group ID attached to its process,
so it can perform any filesystem (read, write, execute) operations
allowed for that group. -->
<permission name="android.permission.BLUETOOTH_ADMIN" >
<group gid="net_bt_admin" />
</permission>
<permission name="android.permission.BLUETOOTH" >
<group gid="net_bt" />
</permission>
<permission name="android.permission.INTERNET" >
<group gid="inet" />
</permission>
<permission name="android.permission.CAMERA" >
<group gid="camera" />
</permission>
<permission name="android.permission.READ_LOGS" >
<group gid="log" />
</permission>
<permission name="android.permission.WRITE_EXTERNAL_STORAGE" >
<group gid="sdcard_rw" />
</permission>
<permission name="android.permission.WRITE_MEDIA_STORAGE" >
<group gid="media_rw" />
</permission>
<permission name="android.permission.ACCESS_MTP" >
<group gid="mtp" />
</permission>
<permission name="android.permission.NET_ADMIN" >
<group gid="net_admin" />
</permission>
<!-- The group that /cache belongs to, linked to the permission
set on the applications that can access /cache -->
<permission name="android.permission.ACCESS_CACHE_FILESYSTEM" >
<group gid="cache" />
</permission>
<!-- RW permissions to any system resources owned by group 'diag'.
This is for carrier and manufacture diagnostics tools that must be
installable from the framework. Be careful. -->
<permission name="android.permission.DIAGNOSTIC" >
<group gid="input" />
<group gid="diag" />
</permission>
<!-- Group that can read detailed network usage statistics -->
<permission name="android.permission.READ_NETWORK_USAGE_HISTOR Y">
<group gid="net_bw_stats" />
</permission>
<!-- Group that can modify how network statistics are accounted -->
<permission name="android.permission.MODIFY_NETWORK_ACCOUNTING ">
<group gid="net_bw_acct" />
</permission>
<!-- ================================================== ================ -->
<!-- ================================================== ================ -->
<!-- ================================================== ================ -->
<!-- The following tags are assigning high-level permissions to specific
user IDs. These are used to allow specific core system users to
perform the given operations with the higher-level framework. For
example, we give a wide variety of permissions to the shell user
since that is the user the adb shell runs under and developers and
others should have a fairly open environment in which to
interact with the system. -->
<!-- Standard permissions granted to the shell. -->
<assign-permission name="android.permission.WRITE_EXTERNAL_STORAGE" uid="shell" />
<assign-permission name="android.permission.SEND_SMS" uid="shell" />
<assign-permission name="android.permission.CALL_PHONE" uid="shell" />
<assign-permission name="android.permission.READ_CONTACTS" uid="shell" />
<assign-permission name="android.permission.WRITE_CONTACTS" uid="shell" />
<assign-permission name="android.permission.READ_CALENDAR" uid="shell" />
<assign-permission name="android.permission.WRITE_CALENDAR" uid="shell" />
<assign-permission name="android.permission.READ_USER_DICTIONARY" uid="shell" />
<assign-permission name="android.permission.WRITE_USER_DICTIONARY" uid="shell" />
<assign-permission name="android.permission.ACCESS_FINE_LOCATION" uid="shell" />
<assign-permission name="android.permission.ACCESS_COARSE_LOCATION" uid="shell" />
<assign-permission name="android.permission.ACCESS_LOCATION_EXTRA_COM MANDS" uid="shell" />
<assign-permission name="android.permission.ACCESS_NETWORK_STATE" uid="shell" />
<assign-permission name="android.permission.ACCESS_WIFI_STATE" uid="shell" />
<assign-permission name="android.permission.BLUETOOTH" uid="shell" />
<!-- System tool permissions granted to the shell. -->
<assign-permission name="android.permission.GET_TASKS" uid="shell" />
<assign-permission name="android.permission.CHANGE_CONFIGURATION" uid="shell" />
<assign-permission name="android.permission.REORDER_TASKS" uid="shell" />
<assign-permission name="android.permission.SET_ANIMATION_SCALE" uid="shell" />
<assign-permission name="android.permission.SET_PREFERRED_APPLICATION S" uid="shell" />
<assign-permission name="android.permission.WRITE_SETTINGS" uid="shell" />
<assign-permission name="android.permission.WRITE_SECURE_SETTINGS" uid="shell" />
<assign-permission name="android.permission.BROADCAST_STICKY" uid="shell" />
<!-- Development tool permissions granted to the shell. -->
<assign-permission name="android.permission.SET_DEBUG_APP" uid="shell" />
<assign-permission name="android.permission.SET_PROCESS_LIMIT" uid="shell" />
<assign-permission name="android.permission.SET_ALWAYS_FINISH" uid="shell" />
<assign-permission name="android.permission.DUMP" uid="shell" />
<assign-permission name="android.permission.SIGNAL_PERSISTENT_PROCESS ES" uid="shell" />
<assign-permission name="android.permission.KILL_BACKGROUND_PROCESSES " uid="shell" />
<!-- Internal permissions granted to the shell. -->
<assign-permission name="android.permission.FORCE_BACK" uid="shell" />
<assign-permission name="android.permission.BATTERY_STATS" uid="shell" />
<assign-permission name="android.permission.INTERNAL_SYSTEM_WINDOW" uid="shell" />
<assign-permission name="android.permission.INJECT_EVENTS" uid="shell" />
<assign-permission name="android.permission.RETRIEVE_WINDOW_CONTENT" uid="shell" />
<assign-permission name="android.permission.SET_ACTIVITY_WATCHER" uid="shell" />
<assign-permission name="android.permission.READ_INPUT_STATE" uid="shell" />
<assign-permission name="android.permission.SET_ORIENTATION" uid="shell" />
<assign-permission name="android.permission.INSTALL_PACKAGES" uid="shell" />
<assign-permission name="android.permission.CLEAR_APP_USER_DATA" uid="shell" />
<assign-permission name="android.permission.DELETE_CACHE_FILES" uid="shell" />
<assign-permission name="android.permission.DELETE_PACKAGES" uid="shell" />
<assign-permission name="android.permission.ACCESS_SURFACE_FLINGER" uid="shell" />
<assign-permission name="android.permission.READ_FRAME_BUFFER" uid="shell" />
<assign-permission name="android.permission.DEVICE_POWER" uid="shell" />
<assign-permission name="android.permission.INSTALL_LOCATION_PROVIDER " uid="shell" />
<assign-permission name="android.permission.BACKUP" uid="shell" />
<assign-permission name="android.permission.FORCE_STOP_PACKAGES" uid="shell" />
<assign-permission name="android.permission.STOP_APP_SWITCHES" uid="shell" />
<assign-permission name="android.permission.MODIFY_AUDIO_SETTINGS" uid="media" />
<assign-permission name="android.permission.ACCESS_DRM" uid="media" />
<assign-permission name="android.permission.ACCESS_SURFACE_FLINGER" uid="media" />
<assign-permission name="android.permission.WAKE_LOCK" uid="media" />
<assign-permission name="android.permission.ACCESS_SURFACE_FLINGER" uid="graphics" />
<!-- This is a list of all the libraries available for application
code to link against. -->
<library name="android.test.runner"
file="/system/framework/android.test.runner.jar" />
<library name="javax.obex"
file="/system/framework/javax.obex.jar"/>
</permissions>
Todo esto está sacado de la rom original de POV que le funciona el acelerometro.