拜電子科技的發展，以往只有專業保修廠會購入昂貴的專業檢修電腦，例如SAAB車系使用的TECH-2，
對於熱血一拜的車友，除了在拍賣或歐美汽車零件商買壹台TECH-2，現在又多了許多評價的選擇，
其中最為車友們熟悉的，當屬VAG車系的VAG-COM。
最近在
01上拜讀「mobilesmith」網友po的兩篇文章：Legend 利用 Torque 軟體當作 OBD-II 車輛診斷系統暨HUD還有軌跡紀錄
及
OBD-II 汽車診斷系統討論
得知有一個平價的solution，透過TECH2介面讀取器，以軟體進行ECU資訊的解碼，
當下立刻在大陸拍賣網站拍下今天的主角：「ELM327 OBD2藍牙讀取器」
此款藍牙讀取器，是使用 Elm Electronics 這間公司所生產的型號327 IC晶片，進行OBD資訊的讀取
此款晶片基本上支援 ISO 15765-4 CAN, SAE J1850 PWM, SAE J1850 VPW, ISO 9141-2, ISO 14230-4 and SAE J1939 等幾種protocols的解譯，原先是設計用來轉接到RS232的介面，
現在網路上則出現了藍牙應用的solution，透過藍牙虛擬的com port來達成無線連接的目的。
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在下拍後，等待兩天後（大陸的快遞業者假日不送件）
今天文章的主角ELM327 終於送到手上
坐飛機過來的
超簡單的「工業包裝」
打看包裝，只有藍牙讀取器本體，用塑膠夾鍊袋裝了
本體上有幾個狀態指示燈
ps. 光碟因為通關考量，所以賣家出貨時就沒附，車友可以自行跟賣家協調用其他方式傳遞
背面
接口特寫
9-3的OBD2接頭在方向機柱右下方
連接時，鑰匙需保持在ACC關閉
接好後，讀取器會亮紅燈
接著在電腦上可以透過藍牙搜尋到名稱為「CBT Dev B」的裝置，
該設備預設之配對密碼為『1234』，
請注意！與常見的0000不同！
完成配對後，就可以開啟ODB2 scan tools的軟體，進行資訊讀取。
網路上有相當多的OBD2 scan tools，以下先用一套freeware進行簡單的示範，
軟體名稱為ScanTool.net 1.2，可以提供簡單的OBD2資訊
以下摘錄OBD2可以提供的資訊項目 （但會因車廠車型與軟體能力，不一定都show的出來）
（資料來源：Generic OBD-II Parameter List, by Palmer Performance Engineering）
| Generic OBD-II Parameters229 parameters | |
|---|---|
| Malfunction Indicator Lamp (MIL) Status | Number of emission-related DTCs stored in this ECU |
| Misfire monitoring support | Fuel system monitoring support |
| Comprehensive component monitoring support | Misfire monitoring status |
| Fuel system monitoring status | Comprehensive component monitoring status |
| Catalyst monitoring support | Heated catalyst monitoring support |
| Evaporative system monitoring support | Secondary air system monitoring support |
| A/C system refrigerant monitoring support | Oxygen sensor monitoring support |
| Oxygen sensor heater monitoring support | EGR system monitoring support |
| Catalyst monitoring status | Heated catalyst monitoring status |
| Evaporative system monitoring status | Secondary air system monitoring status |
| A/C system refrigerant monitoring status | Oxygen sensor monitoring status |
| Oxygen sensor heater monitoring status | EGR system monitoring status |
| DTC that caused required freeze frame data storage | Fuel system 1 status |
| Fuel system 2 status | Calculated Load Value |
| Engine Coolant Temperature | Short Term Fuel Trim - Bank 1 |
| Short Term Fuel Trim - Bank 3 | Long Term Fuel Trim - Bank 1 |
| Long Term Fuel Trim - Bank 3 | Short Term Fuel Trim - Bank 2 |
| Short Term Fuel Trim - Bank 4 | Long Term Fuel Trim - Bank 2 |
| Long Term Fuel Trim - Bank 4 | Fuel Rail Pressure (gauge) |
| Intake Manifold Absolute Pressure | Engine RPM |
| Vehicle Speed Sensor | Ignition Timing Advance for #1 Cylinder |
| Intake Air Temperature | Air Flow Rate from Mass Air Flow Sensor |
| Absolute Throttle Position | Commanded Secondary Air Status |
| Oxygen Sensor Location Bank 1 - Sensor 1 | Oxygen Sensor Location Bank 1 - Sensor 2 |
| Oxygen Sensor Location Bank 1 - Sensor 3 | Oxygen Sensor Location Bank 1 - Sensor 4 |
| Oxygen Sensor Location Bank 2 - Sensor 1 | Oxygen Sensor Location Bank 2 - Sensor 2 |
| Oxygen Sensor Location Bank 2 - Sensor 3 | Oxygen Sensor Location Bank 2 - Sensor 4 |
| Oxygen Sensor Voltage Bank 1 - Sensor 1 | Oxygen Sensor Short Term Fuel Trim Bank 1 - Sensor 1 |
| Oxygen Sensor Voltage Bank 1 - Sensor 2 | Oxygen Sensor Short Term Fuel Trim Bank 1 - Sensor 2 |
| Oxygen Sensor Voltage Bank 1 - Sensor 3 | Oxygen Sensor Short Term Fuel Trim Bank 1 - Sensor 3 |
| Oxygen Sensor Voltage Bank 1 - Sensor 4 | Oxygen Sensor Short Term Fuel Trim Bank 1 - Sensor 4 |
| Oxygen Sensor Voltage Bank 2 - Sensor 1 | Oxygen Sensor Short Term Fuel Trim Bank 2 - Sensor 1 |
| Oxygen Sensor Voltage Bank 2 - Sensor 2 | Oxygen Sensor Short Term Fuel Trim Bank 2 - Sensor 2 |
| Oxygen Sensor Voltage Bank 2 - Sensor 3 | Oxygen Sensor Short Term Fuel Trim Bank 2 - Sensor 3 |
| Oxygen Sensor Voltage Bank 2 - Sensor 4 | Oxygen Sensor Short Term Fuel Trim Bank 2 - Sensor 4 |
| On Board Diagnostic System Type | Oxygen Sensor Location Bank 1 - Sensor 1 |
| Oxygen Sensor Location Bank 1 - Sensor 2 | Oxygen Sensor Location Bank 2 - Sensor 1 |
| Oxygen Sensor Location Bank 2 - Sensor 2 | Oxygen Sensor Location Bank 3 - Sensor 1 |
| Oxygen Sensor Location Bank 3 - Sensor 2 | Oxygen Sensor Location Bank 4 - Sensor 1 |
| Oxygen Sensor Location Bank 4 - Sensor 2 | Power Take Off (PTO) Status |
| Time Since Engine Start | Distance Travelled While MIL is Activated |
| Fuel Rail Pressure relative to manifold vacuum | Fuel Rail Pressure |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 1 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 1 Voltage |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 2 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 2 Voltage |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 3 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 3 Voltage |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 4 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 4 Voltage |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 1 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 1 Voltage |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 2 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 2 Voltage |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 3 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 3 Voltage |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 4 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 4 Voltage |
| Commanded EGR | EGR Error |
| Commanded Evaporative Purge | Fuel Level Input |
| Number of warm-ups since diagnostic trouble codes cleared | Distance since diagnostic trouble codes cleared |
| Evap System Vapor Pressure | Barometric Pressure |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 1 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 1 Current |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 2 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 2 Current |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 3 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 3 Current |
| Oxygen Sensor (Wideband) Bank 1 - Sensor 4 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 1 - Sensor 4 Current |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 1 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 1 Current |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 2 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 2 Current |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 3 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 3 Current |
| Oxygen Sensor (Wideband) Bank 2 - Sensor 4 Equivalence Ratio (lambda) | Oxygen Sensor (Wideband) Bank 2 - Sensor 4 Current |
| Catalyst Temperature Bank 1, Sensor 1 | Catalyst Temperature Bank 2, Sensor 1 |
| Catalyst Temperature Bank 1, Sensor 2 | Catalyst Temperature Bank 2, Sensor 2 |
| Misfire monitoring enable status (for this driving cycle) | Fuel system monitoring enable status (for this driving cycle) |
| Comprehensive component monitoring enable status (for this driving cycle) | Misfire monitoring completion status (for this driving cycle) |
| Fuel system monitoring completion status (for this driving cycle) | Comprehensive component monitoring completion status (for this driving cycle) |
| Catalyst monitoring enable status (for this driving cycle) | Heated catalyst monitoring enable status (for this driving cycle) |
| Evaporative system monitoring enable status (for this driving cycle) | Secondary air system monitoring enable status (for this driving cycle) |
| A/C system refrigerant monitoring enable status (for this driving cycle) | Oxygen sensor monitoring enable status (for this driving cycle) |
| Oxygen sensor heater monitoring enable status (for this driving cycle) | EGR system monitoring enable status (for this driving cycle) |
| Catalyst monitoring completion status (for this driving cycle) | Heated catalyst monitoring completion status (for this driving cycle) |
| Evaporative system monitoring completion status (for this driving cycle) | Secondary air system monitoring completion status (for this driving cycle) |
| A/C system refrigerant monitoring completion status (for this driving cycle) | Oxygen sensor monitoring completion status (for this driving cycle) |
| Oxygen sensor heater monitoring completion status (for this driving cycle) | EGR system monitoring completion status (for this driving cycle) |
| Control module voltage | Absolute Load Value |
| Fuel/Air Commanded Equivalence Ratio | Relative Throttle Position |
| Ambient Air Temperature | Absolute Throttle Position B |
| Absolute Throttle Position C | Accelerator Pedal Position D |
| Accelerator Pedal Position E | Accelerator Pedal Position F |
| Commanded Throttle Actuator Control | Minutes run by the engine while MIL activated |
| Time since diagnostic trouble codes cleared | Compression ignition monitoring supported |
| NMHC catalyst monitoring supported | NOx aftertreatment monitoring supported |
| Boost pressure system monitoring supported | Exhaust gas sensor monitoring supported |
| PM filter monitoring supported | EGR and/or VVT system monitoring supported |
| NMHC catalyst monitoring status | NOx aftertreatment monitoring status |
| Boost pressure system monitoring status | Exhaust gas sensor monitoring status |
| PM filter monitoring status | EGR and/or VVT system monitoring status |
| NMHC catalyst monitoring enable status (for this driving cycle) | NOx aftertreatment monitoring enable status (for this driving cycle) |
| Boost pressure system monitoring enable status (for this driving cycle) | Exhaust gas sensor monitoring enable status (for this driving cycle) |
| PM filter monitoring enable status (for this driving cycle) | EGR and/or VVT system monitoring enable status (for this driving cycle) |
| NMHC catalyst monitoring completion status (for this driving cycle) | NOx aftertreatment monitoring completion status (for this driving cycle) |
| Boost pressure system monitoring completion status (for this driving cycle) | Exhaust gas sensor monitoring completion status (for this driving cycle) |
| PM filter monitoring completion status (for this driving cycle) | EGR and/or VVT system monitoring completion status (for this driving cycle) |
| Type of fuel currently being utilized by the vehicle | Alcohol Fuel Percentage |
| Absolute Evap System Vapor Pressure | Evap System Vapor Pressure |
| Short Term Secondary O2 Sensor Fuel Trim - Bank 1 | Short Term Secondary O2 Sensor Fuel Trim - Bank 3 |
| Long Term Secondary O2 Sensor Fuel Trim - Bank 1 | Long Term Secondary O2 Sensor Fuel Trim - Bank 3 |
| Short Term Secondary O2 Sensor Fuel Trim - Bank 2 | Short Term Secondary O2 Sensor Fuel Trim - Bank 4 |
| Long Term Secondary O2 Sensor Fuel Trim - Bank 2 | Long Term Secondary O2 Sensor Fuel Trim - Bank 4 |
| Fuel Rail Pressure (absolute) | Relative Accelerator Pedal Position |
| Hybrid Battery Pack Remaining Charge | Engine Oil Temperature |
| Fuel Injection Timing | Engine Fuel Rate |
| Emission requirements to which vehicle is designed | Driver's Demand Engine - Percent Torque |
| Actual Engine - Percent Torque | Engine Reference Torque |
| Engine Percent Torque At Idle, Point 1 | Engine Percent Torque At Point 2 |
| Engine Percent Torque At Point 3 | Engine Percent Torque At Point 4 |
| Engine Percent Torque At Point 5 | Power Take Off (PTO) Status |
| Auto Trans Neutral Drive Status | Manual Trans Neutral Gear Status |
| Glow Plug Lamp Status | Mass Air Flow Sensor A |
| Mass Air Flow Sensor B | Engine Coolant Temperature 1 |
| Engine Coolant Temperature 2 | Intake Air Temperature Bank 1, Sensor 1 |
| Intake Air Temperature Bank 1, Sensor 2 | Intake Air Temperature Bank 1, Sensor 3 |
| Intake Air Temperature Bank 2, Sensor 1 | Intake Air Temperature Bank 2, Sensor 2 |
| Intake Air Temperature Bank 2, Sensor 3 | |
