汽车诊断与车载诊断系?OBD)简?精品文档资料 - 百度文库

ʱ : һ 汽车诊断与车载诊断系?OBD)简?精品文档资料 - 百度文库ϿʼĶ

ķ̿ԿCANߵKWP2000Эֶ֧ݴ䣬ҶݵĹ֯ɵģӦò㲻عݵĴͽ̡ 3.2 SAE J1850

SAE J1850 Э֣J1850Ʊ뷽ʽPWM - Pulse Width Modulation J1850ɱƱ뷽ʽVPM - Variable Pulse Width Modulationõı뷽ʽͬŲͬ㣬Ӧò·ͬ

SAE J1850 PWM: ع˾õı׼˫ߴ䣬ͨΪ 41.6Kbps[1]

pin 2: Bus+pin 10: Bus?CߵѹΪ+5VijΪ12ֽڣCRC

÷ƻٲõز·ʣCSMA/NDAĶٲû

SAE J1850VPW:ͨù˾õı׼õߴ䣬ͨΪ10.4Kbps[1]

pin 2:Bus+߿״̬Ϊ͵ƽߵѹΪ+7 Vߵ+3.5VijΪ12ֽڣCRC÷ƻٲõز·ʣCSMA/NDAĶٲû J1850Э涨ڵΪ32 ECU ͳ豸ڵ糤Ϊ40ף

糤Ϊ5ס豸СЧΪ 10.6K ŷЧΪ 500pF

J1850ݴеͨǰ¸ʽģμͼ4

Idle, SOF, DATA_0, ..., DATA_N, CRC, EOD, NB, IFR_1, ..., IFR_N, EOF, IFS,Idle иԪصĶ

Idle߿Уߴڿ״̬ʱκνڵ㶼ռݡ

SOF֡ʼ־ CRC 롣 DATA_Nݡ

EODݽ־֡ͷ EOD ʾݷͽ

NB׼λ VPW 뷽ʽЧ EOF֡־IFR֡ڿӦ IFS֡ڷָ־ CRCCRC Уλ 3.3 CAN

CAN 2080ſʼγɺͷչһ߼BOSCH˾2090CAN߱ύΪʱ׼

CANЭһֿϵͳеͨ

ͨЭ飬ڳܺͳʹܵĹͬϸߵҲ㳵ڲϵͳܹ CANΪӸͨϵͳΪĿзģصԪߣ˽ṹ໥ӡCAN ܹʹöʣ˫ߡ˵ȣõ˫ߡCANĴٶɴ 1Mbit/s

CANֲͬ֡ʽ׼֡ʽչ֡ʽ֮ͬΪ׼֡Ϊ11λʶչ֡29λʶͼ5ͼ6 ʾ

CANֲͬ͵֡֡Զ֡֡͹֡֡Զ֡ʹñ׼չָʽ

CANЭص[3]

1߿ʱӵϵĸԪԿʼϢһʼϢĵԪ÷ȨԪͬʱʼͣȼĵԪ÷Ȩ 2Ĵ䣺еĶԤĸʽ䡣 3ϵͳԣӵϵĵԪûڵַʶϢˣһԪӵϻʱҪıκ豸ӲӦò㡣

4ͨٶȣ趨ΪͨٶԿʺĴСһУеԪʹͳһͨٶȡ

5Զ󣺿Ԫ͡Զ֡ݴ䡣

6д⡢֪ͨʹָܡ 7룺CANʱϺͳϵĹܣڽ׳ϵĵԪȼԷֹ谭Ԫͨš

8ӣCANͬʱӶԪȻʵʿߵĵԪܵɺӳʱơ УJ2480ISO15765Э鶼ǻCANġKWP2000SAE J1850綼𽥱CAN档

4ϵͳй

200545գһַܾ׼ȾŷֵйIIIIV׶ΣGB18352.3-2005׼ΪȾŷű׼OBDΪǿҪ״γҹķ׼С

׼ͨ޸IJŷˣEU70/220/EECָ޶98/69/EC ָԼֹ2003/76/ECĸ޶ָйؼݲġҪ޸ݰM1M2೵͵ķ顢ȼϵļҪ5棬OBDֻհŷ˵ı׼EOBD 5ϼչ

5.1 չеOBD-III

OBD-IIȻϳŷعϣ޷֤ʻ߽MILľ沢Գϼʱ޸һOBDϵͳҪص⡣OBD-IIIߴϢΪҪܹСͳշϵͳͨƶͨ硢ͨŻGPSϵͳVIN뼰λõϢԶϱƽ̨Ÿݸóŷĵȼ䷢ָȥδά޵Ľ顢ŷʱ޵ȡЩϢڸطɹŷȾij߽гͷ[9]

OBD-IIIҪͨѶ׼ͷIJϳ죬OBDϵͳϹܱ׼ȷԺͿɿҲһߵҪ󡣿룬OBD-IIIijӦãϷģʽľ޴

5.2 µͨЭ֧

ϵͬͷxxxxx#qq.com(#滻Ϊ@)