OBD-II通讯协议OBD-II Network Standards» J1850 PW– Adopted by GM; also known as Class 2.– Adopted by Chrysler (known as J1850).– Some references to PW mode heard about in regards to Toyota (and Honda ?). – 10.4 kbps, single wire.» J1850 PWM– Adopted by Ford; also known as Standard Corporate Protocol (SCP).– Also seen in some Mazda products.– Some references to PWM mode heard about in regards to Mitsubishi.– 41.6 kbps, two wire balanced signal.» ISO 9141 and ISO 9141-2 (also known as ISO 9141 CARB)– Seen in some Chrysler and Mazda products.– Seems to be more common in Europe.– 10.4 kbps, single wire.OBDII 通讯协议obdii generic communication protocols by manufacturerRecently I tried to install my product on Peuzeot(406 or somethingsimilar). There wasKWP 2000 bus. I tried to get the speed alue from the bus by sendingthe following string0xc2 0x33 0xf1 0x01 0x0d 0xf4.On responce I receied two answers from 2 different ECUs:1) 0x83 0xf1 0x10 0x7f 0x01 0x12 0x161) 0x83 0xf1 0xa4 0x41 0x0d 0x00 0x66The first ECU sent me NACK(This response code indicates that the requested action will not betaken because the serer (ECU) does not support the arguments of therequest message or the format of the argument bytes do not match the prescribed format for the specified serice.)My question is: if there was something wrong with the arguments of therequest message, the second ECU also should not understand therequest, bit it did !And the second question is: why the first ECU did send the negatieanswer. If you look at the j1979 PDF you will find there that "If anECU does not support any of the PIDs requested it is not allowed tosend a negatie response message".OBD 信息：我理解的OBD-II标准诊断插座列表我理解的obd-ii标准诊断插座列表端子号称端子接线---------------------------------------------------------------------4 搭铁16 蓄电池正极，9-127，15 资料数据传输线（iso 9141-2）5 信号反馈线搭铁2 sae j1850数据输送线10 sae制造厂数据输送线举一实例；捷达前卫诊断座t16中；就有16 4 7三个端子按以上要求接线。

EOBD 欧洲标准新的european obd 诊断坐连接标准dlc-j1962=============================================== =================================pin 1 ......sae j2411, gm single wire can;通用公司单线can-buspin 2 ......iso 11519-4 (bus+)(sae j1850), 和10号脚同时使用, 41.6 kbps pwm脉宽调制单线用法:只用2号脚1根线通讯10.4 kbps pw可变脉宽调制byte header + crc,no "checksum" or "inter-byte separation" (in frame response byte ?)pin 3 ...... chrysler, ccd+ (not obd) ;克莱斯勒ccd-bus网线h 线pin 4 ...... 底盘地chassis groundpin 5 ...... 逻辑地signal groundpin 6 ...... iso 15765-4;can-bus 高速诊断线(h 线) ,250/500 kbit/spin 7 ....... kwp1281或kwp2000 协议诊断线(k线), 波特率10400/多数厂家默认kpw2000诊断线pin8 ........ 点火开关打开有电ig+;点火开关on/off 状态识别用途pin9 ........ 7号脚不方便用时,启用*kwp1281或kwp2000 协议诊断线(k线), 波特率10400 pin10 ....... iso 11519-4 (bus-)(sae j1850), 和2号脚同时使用, 41.6 kbps pwm脉宽调制pin 11 ...... chrysler, ccd- (not obd) ;克莱斯勒ccd-bus网线l 线pin 12 ...... * k 线制造厂保留用pin 13 ...... * k 线制造厂保留用pin 14 ...... iso 15765-4;can-bus 高速诊断线(l 线) ,250/500 kbit/spin 15 ...... kwp1281或kwp2000 协议诊断线(k线);7p不够用或控制单元过多时启用pin 16 ...... 长火线bat+OBDII协议Connected ISO9141 protocol to ECU Address 0x33 (protocol key bytes 0x08, 0x08) Direction Header bytes Payload bytes Checksum Byte MeaningTester -> Car 0x68 0x6a 0xf1 0x01 0x00 0xC4 Request (Serice 1, Parameter 0)Car -> Tester 0x00 0x00 Garbage!!Tester -> Car 0x68 0x6a 0xf1 0x01 0x00 0xC4 Request (Serice 1, Parameter 0)Car -> Tester 0x00 0x00 0x00 Garbage!!Tester -> Car 0x68 0x6a 0xf1 0x01 0x00 0xC4 Request (Serice 1, Parameter 0)Car -> Tester 0x00 0x00 0x00 0x00 Garbage!!Tester -> Car 0x68 0x6a 0xf1 0x01 0x00 0xC4 Request (Serice 1, Parameter 0)Car -> Tester 0x00 0x00 0x00 0x00 0x00 Garbage!!Tester -> Car 0x68 0x6a 0xf1 0x02 0x00 0x00 0xC5 Request (Serice 2, Parameter 0)Car -> Tester 0x00 0x00 0x00 0x00 0x00 0x00 Garbage!!It successfully negotiated the initialization of an ISO9141 protocol session(by responding key bytes "0x08, 0x08"), and then went berserk on me... eery time I tried this,it has behaed the same way - useless. After a successful initialization,it just responds "zeros" back to eery request,******************************************************************************* **************************标准OBD-II 有3种1. ISO 使用ISO-9141 (借用BOSH)使用J1962-7 单线通讯电平高低表示逻辑"1" 和"0"2. SAE J1850 (借用GM)使用J1962-2 单线通讯脉冲宽度表示逻辑"1" 和"0"3. SAE J1850 (借用FORD)使用J1962-2/J1962-10 2线通讯可变脉宽.脉冲宽度表示逻辑"1" 和"0"******************************************************************************* **************************标准OBD-II 诊断之ISO标准部分使用ISO9141物理连接定义在J1962 的7号脚就是我们常说的K 线标准OBD-II 协议ISO-9141 特点PCM动力系统5波特率地址码33H 协议字KB1:08H;协议字KB2:08H;解码器用KB2取反$F7H确认收到$08 $08protocol to ECU Address 0x33 (protocol key bytes 0x08, 0x08) 解码器地址码$F1说话对象首字节工作字节校验和字节含意============ ======== ================= ===== ========================解码器-> 车68 6a f1 01 00 C4 请求(命令1, 参数0)车-> 解码器00 00 无意义解码器-> 车68 6a f1 01 00 C4 请求(命令1, 参数0)车-> 解码器00 00 00 无意义解码器-> 车68 6a f1 01 00 C4 请求(命令1, 参数0)车-> 解码器00 00 00 00 无意义解码器-> 车68 6a f1 01 00 C4 请求(命令1, 参数0)车-> 解码器00 00 00 00 00 无意义解码器-> 车68 6a f1 02 00 00 C5 请求(命令2, 参数0)Car -> 解码器00 00 00 00 00 00 无意义三个基本通讯协议：1 iso 9141通讯协议电路。