Service Training Edition European On Board Diagnosis. Trainer information (GB)

Transcription

1 13.01 Ediion European On Board Diagnosis Trainer informaion (GB)

2 Table of Conens Chaper Page 1 Inroducion Legal Basis Deadline for inroducion Transiion period Overview K83 exhaus gas indicaor ligh Diagnosis inerface Monioring 6 2 New vehicle sysems Broad-band lambda probe Operaion Design Elecrical exhaus gas recirculaion Inegraed shaf seal sensor 13 3 EOBD versions Basic forms of he engine conrol Inducion pipe pressure sysems Air mass sysems Vehicles, engines and engine conrol unis Engine conrol unis and diagnoses 17 K-VK-36/rc/TI13_01gb.doc 2/

3 Table of Conens Chaper Page 4 Diagnosic procedure Conrol limis diagnosis of he pos-caalyic converer Movemen diagnosis of he pos-caalyic converer Fuel ank ven line modulaion diagnosis Combusion misfiring Insananeous analysis procedure Elecrical exhaus gas recirculaion pressure diagnosis CAN daa bus daa diagnosis Secondary air sysem flow diagnosis Charge pressure limis diagnosis 26 5 Self-diagnosis Readiness code Displaying readiness code Creaing readiness code Generic scan ool (OBD daa display erminal) VAS 5051 vehicle diagnosis, measuring and informaion sysem Displaying readiness code Performing shor rips 31 K-VK-36/rc/TI13_01gb.doc 3/

4 1 Inroducion 1.1 Legal Basis On Ocober 13, 1998, he European Union passed he EU guideline 98/69EC which direcs all member saes o inroduce he EOBD. This guideline was implemened o naional law in he Federal Republic of Germany. The inroducion of EOBD is no direcly conneced o he emissions sandard of he European Union (EU II, EU III, EU IV) or of he Federal Republic of Germany (D2, D3, D4). Therefore, he deadline for he inroducion and he associaed ransiion period mus be considered o be independen of he emissions sandard Deadline for inroducion The auomobile indusry receives only an iniial accepance for he new vehicle models as of January 1, 2000, when hese have an EOBD Transiion period The ransiion period affecs vehicle models which have received an iniial accepance before December 31, 1999 and have fulfilled he EU II, D3 or D4 emissions sandard. The buyer may sill regiser hese vehicles unil December 31, Afer his dae, even he vehicle models already in use are required o have an EOBD. K-VK-36/rc/TI13_01gb.doc 4/

5 The EOBD legislaion does no affec vehicles which he buyer has regisered before December 31, Iniial accepances in he auomobile indusry New vehicle models wihou OBD New vehicle models wih OBD Year 2000 Year 2001 New vehicles wihou OBD New vehicles wihou OBD (wih EU II, D3, D4) New vehicles wih OBD Regisraion of buyers new vehicles 1.2 Overview The obvious componens of he EOBD are he K83 exhaus gas indicaor lighs and he diagnosis inerface in he passenger comparmen. All furher funcions and diagnoses will be performed by he engine conrol uni auomaically wihou he driver being aware of he consan checking of his emissions-relevan vehicle echnics K83 exhaus gas indicaor ligh If an error should occur in he vehicle which impairs he emissions qualiy, he error is sored in he faul memory and he exhaus gas indicaor ligh is urned on. If he caalyic converer could be damaged by a combusion misfiring, he exhaus gas indicaor ligh flashes. K-VK-36/rc/TI13_01gb.doc 5/

6 1.2.2 Diagnosis inerface The sored EOBD daa can be rerieved via he diagnosis inerface. The error codes have been sandardised, so ha he daa can be capured by any Generic Scan Tool (OBD daa display erminal). The diagnosis inerface mus be wihin easy reach of he driver s sea Monioring EOBD moniors: he elecrical funcioning of all componens which are of imporance for he emissions qualiy. he operaion of all vehicle sysems which affec he emissions qualiy (e.g. lambda probes, secondary air sysem). he operaion of he caalyic converer. when he engine misfires. he CAN daa bus. he error-free operaion of he auomaic gearbox. K-VK-36/rc/TI13_01gb.doc 6/

7 2 New vehicle sysems 2.1 Broad-band lambda probe Broad-band lambda probe I Rich mixure Lean mixure The broad-band lambda probe (LSU universal lambda probe) is a new generaion of lambda probes which is used as a pre-caalyic converer probe. The oupu of he lambda value no longer appears as a disconinuous, increasing volage curve, raher an almos linear increase in curren. In his manner, he lambda value can be measured over a larger measuring range (broad-band). Convenional finger probes (LSH - lambda probe heaing) or planar lambda probes (LSF planar lambda probe) are also called jump probes due o heir disconinuous volage curves. Curren I Lambda U Planar lambda probe Rich mixure Lean mixure A planar lambda probe (LSF) is used for he poscaalyic converer probe. The disconinuous measuring range of a planar lambda probe wih lambda value of approx. = 1 is sufficien for he monioring funcion of he poscaalyic converer probe. Volage U Lambda K-VK-36/rc/TI13_01gb.doc 7/

8 2.1.1 Operaion The lambda value for linear lambda probes is no deermined by a change of volage, bu by a change in curren. The physical processes are sill he same. 5 1 Exernal air 2 Probe volage 3 Engine conrol uni 4 Elecrodes 5 Exhaus A 450 mv Planar lambda probe The key elemen is a ceramic body which is coaed on boh sides (Nerns cell). This coaing akes over he funcion of elecrodes, where one elecrode layer comes ino conac wih exernal air and he oher wih he exhaus. A poenial difference is esablished beween he elecrodes by differing concenraions of oxygen in he exernal air and he exhaus. This volage will be evaluaed for deerminaion of he lambda value in he engine conrol uni. Broad-band lambda probe This probe also produces a poenial difference wih he help of wo elecrodes which is he produc of he differing concenraions of oxygen. I is differen o he disconinuous lambda probe, in ha he volage of he elecrodes is kep consan. This process is carried ou by a miniaure pump (pump cell) which supplies he elecrodes on he exhaus side wih enough oxygen o ensure ha he volage beween he elecrodes remains a consan 450 mv. The curren consumpion of he pump is convered by he engine conrol uni ino a lambda value. 1 6 Miniaure pump (Pump cell) 7 Pump curren 8 Measuring area 9 Diffusion channel 4 K-VK-36/rc/TI13_01gb.doc 8/

9 Conrol example 1 The fuel-air mixure becomes leaner. This means ha he oxygen concenraion in he exhaus increases and ha he pump cell pumps more 0 oxygen ino he measuring area han can escape hrough he diffusion channel. This changes he A oxygen raio in respec of he exernal air and he volage beween he elecrodes drops. 450 mv 0 A 450 mv In order o re-esablish he volage of 450 mv beween he elecrodes, he oxygen conen on he exhaus side mus be reduced. The pump cell mus hen pump less oxygen ino he measuring area. The pump performance is hen reduced. The engine conrol uni convers he curren consumpion of he pump cell ino a lambda value and changes he mixure composiion accordingly. K-VK-36/rc/TI13_01gb.doc 9/

10 Conrol example 2 When he fuel-air mixure becomes oo rich, he oxygen conen in he exhaus decreases, he pump cell delivers less oxygen ino he measuring area 0 and he volage of he elecrodes increases. In his case, more oxygen escapes hrough he A diffusion channel han he pump cell delivers. 450 mv 0 A The pump cell mus increase is capaciy, so ha he oxygen conen increases in he exernal air chamber. The elecrode volage is rese o he value of 450 mv in he process and he curren consumpion of he pump is convered ino a lambda conrol value by he engine conrol uni. 450 mv The pump cell operaes by a purely physical process. Due o a posiive volage of he pump cell, negaive oxygen ions are drawn hrough he oxygen-permeable ceramic. The linear lambda probe and he engine conrol uni make up one sysem. The lambda probe mus be suied o he engine conrol uni. K-VK-36/rc/TI13_01gb.doc 10/

11 2.1.2 Design The previously menioned componens are only a few millimeres long on he broad-band lambda probe. Cross-secion of he probe elemen Oxygen pump cell wih elecrodes 2 Nerns pump cell wih elecrodes 3 Probe heaing 4 Exernal air channel 5 Measuring area 6 Diffusion channel When he broad-band lambda probe has o be replaced, he cable and plug mus also be replaced, because he probe elemen, he cable and he plug are muually harmonised. K-VK-36/rc/TI13_01gb.doc 11/

12 2.2 Elecrical exhaus gas recirculaion There is only one valve for he elecrical exhaus gas recirculaion: Exhaus gas recirculaion valve N18 This valve is direcly conrolled by he engine conrol uni and elecromagneically adjuss he opening sroke for he exhaus gas recirculaion. The poeniomeer for G212 exhaus gas recirculaion repors o he engine conrol uni he acual opening sroke of he valve Engine conrol uni 2 Exhaus gas recirculaion valve 3 Air ven The air ven may only be conneced o pure air (filered exernal air). When he exhaus gas recirculaion valve is replaced, he seal mus be replaced a he same ime. K-VK-36/rc/TI13_01gb.doc 12/

13 2.3 Inegraed shaf seal sensor A new generaion of engine speed sensors G28 will be used in some engines - he Inegraed Shaf Seal Sensor. The sensor is siuaed in a seal flange for he crankshaf on he gearbox side of he engine. The sensor gearwheel (60-2 eeh) is pressed ino precisely he correc posiion on he crankshaf. The seal flange and sensor are produced by wo differen manufacurers and, for his reason, can differ in heir designs. Crankshaf Engine speed sensor G28 Gearbox side Engine side Sensor gear Seal flange Crankcase K-VK-36/rc/TI13_01gb.doc 13/

14 3 EOBD versions 3.1 Basic forms of he engine conrol A basic division is made beween he engine managemen sysems in he way, in which operaional condiions are deermined in he inducion pipe (air mass or inducion pipe pressure). This division does no relae o specific manufacurers of engine conrol unis because boh forms are usually available. The inake air quaniy or he inducion pipe pressure is required for he calculaion of - he igniion ime, - he fuel injecion ime and - he EOBD monioring of he fuel ank ven line and exhaus gas recirculaion sysems Inducion pipe pressure sysems The inake air quaniy is deermined by he inducion pipe G71 sensor for hese engine Inducion pipe pressure sensor managemen sysems. An air mass meer G70 is no included in hese sysems. Igniion Fuel injecion EOBD K-VK-36/rc/TI13_01gb.doc 14/

15 3.1.2 Air mass sysems The air mass meer G70 akes over he ask of deermining he inake air quaniy. For his reason, he inducion pipe pressure sensor G71 is no necessary. Air mass meer Igniion Fuel injecion EOBD Air mass meers G70 and inducion pipe pressure sensors G71 are insalled in urbo engines, because he inducion pipe pressure meer needs o also measure he charge pressure Vehicles, engines and engine conrol unis Nex, he various engine conrol unis and engine managemen sysems are assigned o he plaforms wih he associaed vehicles and engines. Plaform A00: VW Lupo Plaform A0: VW Polo Engine Code Engine managemen Air quaniy deecion 1.0l Bucke appe perol engine 37 kw ALL Bosch Moronic ME Inducion pipe pressure 1.4l Bucke appe perol engine 44 kw Bosch Moronic ME Inducion pipe pressure 1.4l 4V Perol engine 55 kw AKQ Magnei Marelli 4LV Inducion pipe pressure 1.4l 4V Perol engine 74 kw ANM Magnei Marelli 4LV Inducion pipe pressure 1.6l Perol engine 88 kw Magnei Marelli 4LV Inducion pipe pressure 1.6l Perol engine 92 kw Siemens Simos 3 Air mass K-VK-36/rc/TI13_01gb.doc 15/

16 Plaform A: VW Golf, VW Bora, VW New Beele Engine Code Engine managemen Air quaniy deecion 1.4l 4V Perol engine 55 kw AKQ Bosch Moronic ME Inducion pipe pressure 1.6l Perol engine 74 kw AKL Siemens Simos 3 Air mass 1.8l 5V Turbo perol engine 110 kw AGU Bosch Moronic ME 7.5 Air mass 2.3l V5 Perol engine 110 kw AGZ Bosch Moronic ME 7.1 Air mass 2.8l VR6-4V Perol engine 142 kw Bosch Moronic ME 7.1 Air mass 2.0l Perol engine AEG crossflow cylinder head 85kW (New Beele only) Bosch Moronic M Air mass Plaform B: VW Passa, VW Sharan Engine Code Engine managemen Air quaniy deecion 1.6l Perol engine 74 kw AHL Siemens Simos 3 Air mass 1.8l 5V Perol engine 92 kw ADR Bosch Moronic ME 7.5 Air mass 1.8l 5V Turbo perol engine 110 kw AEB Bosch Moronic ME 7.5 Air mass 2.3l V5 Perol engine Bosch Moronic ME 7.1 AGZ 110 kw Air mass 2.8l VR6-4V Perol engine 142 kw ACK Bosch Moronic ME 7.1 Air mass 2.9l VR6-4V Perol engine 150 kw (Sharan only) Bosch Moronic ME 7.1 Air mass 2.0l Perol engine 85 kw (Sharan only) Bosch Moronic ME 7.1 Air mass T4 Engine Code Engine managemen Air quaniy deecion 2.0l Perol engine 85 kw Bosch Moronic ME 7.1 Air mass 2.3l Engine wih 5 cylinders in line 115 kw Siemens Simos 3 Air mass 2.9l VR6-4V Perol engine 150 kw Bosch Moronic ME 7.1 Air mass K-VK-36/rc/TI13_01gb.doc 16/

17 3.2 Engine conrol unis and diagnoses By using he following able, you should be able o see more clearly which EOBD diagnosis has already been described in SSP 175 and which diagnosis will be described in his rainer informaion repor. EOBD diagnosis SSP 175 Page Comprehensive componens monioring Volage curve shif and adapaion of he pre-caalyic converer probe Lambda probe heaing diagnosis Conrol limis diagnosis of he pos-caalyic converer 18 Movemen diagnosis of he pos-caalyic converer 19 Fuel ank ven line flow diagnosis Fuel ank ven line modulaion diagnosis 20 Combusion misfire Irregular running procedure Combusion misfire Insananeous analysis procedure 21 Exhaus gas recirculaion pressure diagnosis 23 Elecric hrole acivaion SSP 210 CAN daa bus - daa diagnosis 24 Secondary air - flow diagnosis 25 Charge pressure limis diagnosis 26 Please noe ha he differen engine conrol unis use differen diagnosic procedures. K-VK-36/rc/TI13_01gb.doc 17/

18 4 Diagnosic procedure 4.1 Conrol limis diagnosis of he pos-caalyic converer Lean fuel-air mixure and correc regulaion m 1 U OK The lambda conrol value has prescribed conrol limis. If hese conrol limis are exceeded, he EOBD assumes ha here is an error in he poscaalyic converer probe or in he exhaus sysem (air leak). The pos-caalyic converer probe deecs an oxygen increase in he exhaus emissions hrough a drop in volage and indicaes his o he engine conrol uni. The engine conrol uni hen increases he lambda conrol value and he fuel-air mixure is made richer. The volage in he pos-caalyic converer is raised and he engine conrol uni can also lower he lambda conrol value again. 1 Engine conrol uni 2 Pos-caalyic converer probe m Lambda conrol value U Volage Time 2 Lean fuel-air mixure and exceeding he conrol value limi m U no OK In his case oo, he pos-caalyic converer probe deecs an oxygen increase in he exhaus emissions hrough a drop in volage and indicaes his o he engine conrol uni. The engine conrol uni hen increases he lambda conrol value and he fuel-air mixure is made richer. Despie he fac ha his mixure is made richer, he probe s volage remains low, due o he error, and he engine conrol uni coninues o increase he lambda conrol value unil he conrol limi is exceeded, hus enabling he error o be recognised. K-VK-36/rc/TI13_01gb.doc 18/

19 4.2 Movemen diagnosis of he pos-caalyic converer The pos-caalyic converer probe s operabiliy is also moniored. The engine conrol uni checks he probe s signals during acceleraion and deceleraion. During acceleraion, he fuel-air mixure becomes richer, he oxygen concenraion in he exhaus gas falls and he probe volage mus increase. The siuaion is jus he opposie during deceleraion. The fuel feed is urned off, he oxygen concenraion in he exhaus gas rises and he probe volage mus decrease. If he expeced reacion of he poscaalyic converer does no occur, he engine conrol uni will deec ha he pos-caalyic converer probe is defecive. Vehicle acceleraion, as an example OK no OK 1 v U v U 2 1 Engine conrol uni 2 Pos-caalyic converer probe v U Vehicle speed Volage Time K-VK-36/rc/TI13_01gb.doc 19/

20 4.3 Fuel ank ven line modulaion diagnosis This diagnosis performs checks a is own es inervals. The solenoid valve for he acivaed carbon filer sysem will be opened more and less by he engine conrol uni in a prescribed rhyhm. The inducion pipe pressure "modulaed" by his is deeced by he inducion pipe pressure sensor and evaluaed by he engine conrol uni. OK no OK 1 a P a P Engine conrol uni 2 Fuel ank 3 Acivaed carbon filer 4 Solenoid valve for acivaed carbon filer sysem 5 Inducion pipe pressure sender a P Solenoid valve opening sroke Time Pressure K-VK-36/rc/TI13_01gb.doc 20/

21 4.4 Combusion misfiring Insananeous analysis procedure The insananeous analysis procedure, as well as he irregular running procedure deec he cylinderselec combusion misfiring from he engine speed sensor signal G28 and he Hall probe G40. The difference lies in he evaluaion of he engine speed signal. The insananeous analysis procedure compares he irregular speed, produced by he igniion and he compression, by se calculaions in he engine conrol uni. The basis for hese calculaions is he orque which depends on he load and engine speed, he ineria and he resuling engine speed characerisic. The engine s orque flucuaions hereby calculaed are more indicaive han he resuls of he combusion irregulariy procedure (combusion misfire yes/no). However, he engine speed characerisic mus be analysed for each engine ype and sored in he engine conrol uni. For purposes of simplificaion, only he 1 s cylinder will be considered in his example. Irregular engine speed rpm During he compression, he engine s movemen energy is used o compress he fuel-air mixure. The engine s speed decreases. rpm Engine speed Time K-VK-36/rc/TI13_01gb.doc 21/

22 rpm Igniion occurs afer compression and he engine speed will be acceleraed. In his manner, he engine speed flucuaes during each combusion due o compression and igniion. When all four cylinders are considered, he individual speed flucuaions overlay and yield a resulan characerisic. This curve is measured by he engine speed sensor and is checked by he engine conrol uni by he compuaion wih he characerisic values for he engine. Combusion misfiring deecion using he engine speed signal OK no OK rpm rpm If he EOBD exhaus gas limis are exceeded due o combusion misfiring, he exhaus gas indicaor ligh remains illuminaed. If, however, he caalyic converer may be damaged due o he combusion misfiring and he load speed is sill wihin he dangerous range, he exhaus gas indicaor ligh flashes and he appropriae cylinder s fuel feed is urned off. K-VK-36/rc/TI13_01gb.doc 22/

23 4.5 Elecrical exhaus gas recirculaion pressure diagnosis When exhaus gas flows ino he inducion pipe, he inducion pipe pressure sensor G71 deecs an increase in pressure (less pressure). The engine conrol uni compares he increase in pressure in he inducion pipe wih he admied exhaus gas quaniy and can deermine from his wheher he exhaus gas recirculaion (EGR) is funcioning properly. This diagnosis is only performed during deceleraion because he fuel injecion is urned off for he measuremen due o he fac ha i is a disurbance and he engine s inake capaciy is very high. OK no OK 1 P+ P+ P- P Engine conrol uni 2 Exhaus gas recirculaion valve 3 Inducion pipe pressure sensor P+ Overpressure P- Low pressure Time K-VK-36/rc/TI13_01gb.doc 23/

24 4.6 CAN daa bus daa diagnosis Each engine conrol uni recognises he elecronic componens which exchange informaion via he CAN daa bus in each vehicle. If he minimum number of repors for a componen is missing, an error is deeced and sored. 2 1 OK CAN daa bus operabiliy All conneced componens (in his case, conrol unis) regularly send messages o he engine conrol uni. I recognises ha no expeced repors are missing and ha daa exchange is funcioning properly. A B C no OK CAN daa bus inerruped A componen canno send informaion o he engine conrol uni. The engine conrol uni deecs he missing informaion, idenifies he affeced componen and sores a corresponding error. A B C 1 Engine conrol uni 2 CAN daa bus A-C Various conrol unis in he vehicle K-VK-36/rc/TI13_01gb.doc 24/

25 4.7 Secondary air sysem flow diagnosis Since he inroducion of he broad-band lambda probe, he pre-caalyic converer probe signal has been used for he checks because he broad-band lambda probe delivers more deailed measuremen resuls han a planar lambda probe, for example. The delivered air mass is compued hen from he lambda difference (lambda, before and during he secondary air delivery). OK no OK 1 2 I I Engine conrol uni 2 Relay for secondary air pump 3 Secondary air valve 4 Secondary air pump 5 Combinaion valve 6 Pre-caalyic converer probe I Probe curren Time K-VK-36/rc/TI13_01gb.doc 25/

26 4.8 Charge pressure limis diagnosis The charge pressure in urbo engines is checked o deermine wheher he maximum permissible charge pressure wihin he framework of he EOBD has been exceeded. 1 P OK The charge pressure limi has been exceeded The maximum permissible charge pressure has been exceeded due o an error in he charge pressure regulaion. The inducion pipe pressure sensor repors he acual charge pressure o he engine conrol uni and he engine conrol uni recognises he error. 2 P Pressure Time P no OK The proecion funcion is riggered Signalling and soring he error is no sufficien in his case. The exhaus gas urbo charger mus be urned off, so ha he engine is no damaged. For his purpose, he urbo charger s "wase gae" hrough which he propulsive exhaus gases are reroued is opened. 1 Engine conrol uni 2 Solenoid valve for limiing charge pressure 3 Exhaus gas urbo charger wih charge pressure regulaing valve 4 Wase gae 5 Inducion pipe pressure sensor K-VK-36/rc/TI13_01gb.doc 26/

27 5 Self-diagnosis 5.1 Readiness code All elecric componens will be coninuously checked o deermine wheher hey are operaing properly wihin he framework of he EOBD. Addiionally, enire sysems (e.g. exhaus gas recirculaion) will also be checked by diagnosic procedures which are no coninuously acive. In order o check wheher hese diagnoses have been performed, he readiness code is se. I consiss of an 8-digi numerical code where each place can be occupied by 0 (diagnosis performed) or 1 (diagnosis no performed). The readiness code is se by he engine conrol uni, if: - he readiness code has been deleed. - an error occurred whereupon he diagnoses will be carried ou again. The readiness code is no an indicaor of errors which have occurred. I only saes wheher he diagnoses were performed. If he coninuous diagnoses have no caused any error enries, hen he sysems are working properly. The faul memory should no be erased unnecessarily because he readiness code would also be rese or erased in he process. Since all diagnoses are no available in all vehicles, he unused readiness code digis are usually se o 0. K-VK-36/rc/TI13_01gb.doc 27/

28 5.1.1 Displaying readiness code There are wo ways o read ou he readiness code, - wih any generic scan ool of your choice (OBD daa display erminal) - or wih he VAS 5051 vehicle diagnosis, measuring and informaion sysem Creaing readiness code The readiness code can only be creaed by performing he diagnoses. There are hree opions for his: - o perform a MVEG driving cycle. In normal operaion, i is no usually possible o carry ou an MVEG driving cycle afer performing repairs. - o perform a prescribed check rouine (shor rip) for each relevan vehicle sysem wih he help of he VAS 5051 diagnosis sysem. - o drive for a long enough period of ime in average driving mode. 5.2 Generic scan ool (OBD daa display erminal) I mus be possible o display errors and daa relevan o exhaus gas deeced by he engine conrol uni wihin he EOBD on any OBD daa display erminal. Therefore, he recognised errors are sored using an SAE code. This SAE code is used by all OBD sysems. K-VK-36/rc/TI13_01gb.doc 28/

29 SAE code: - P0xxx: Codes which he SAE (Sociey of Auomoive Engineers) have esablished wih se error exs. (Same for all auomobile manufacurers) - P1xxx: Codes prescribed by he auomobile manufacurers which mus be regisered wih he appropriae auhoriies. (Various meanings for he various auomobile manufacurers). I may only be conneced wih he diagnosis inerface in he passenger comparmen for he sar-up procedure of an OBD daa display erminal. The communicaion beween he engine conrol uni and he OBD daa display erminal is auomaically esablished. You will find he error ables for he SAE codes in he workshop manuals wih he respecive engine conrol uni. K-VK-36/rc/TI13_01gb.doc 29/

30 An OBD daa display erminal makes he following funcions possible. - Mode 1: Displaying diagnosis daa relevan o exhaus gas (IST daa, readiness code). - Mode 2: Displaying operaional condiions which occurred during he soring of an error. (Only occupied when an error has occurred.) - Mode 3: Displaying errors relevan o exhaus gas which caused he exhaus gas indicaor ligh o be acivaed. - Mode 4: Deleing error codes, readiness codes and operaional condiions (mode 2). - Mode 5: Displaying lambda probe signals. - Mode 6: Displaying readings from sysems no consanly being moniored (e.g. secondary air sysem, fuel ank ven line sysem). - Mode 7: Displaying errors which have no ye acivaed he exhaus gas indicaor ligh. - Mode 8: No ye assigned in Europe. - Mode 9: Displaying vehicle informaion (e.g. Iden. no., engine code, engine conrol uni ype, sofware idenificaion, sofware check sum). K-VK-36/rc/TI13_01gb.doc 30/

31 5.3 VAS 5051 vehicle diagnosis, measuring and informaion sysem You can display he readiness code wih he VAS 5051 and perform he individual shor rips for he vehicle sysems required for he creaion of he readiness code. In addiion o he funcions of he OBD daa display erminal, he VAS 5051 provides you wih furher adjusmen, diagnosis and faul isolaion funcions. The faul isolaion can be opimised by having access o all perinen engine daa Displaying readiness code - Turn on he igniion. - Selec he vehicle self-diagnosis mode. - Selec he engine conrol uni wih he address word Selec he readiness code funcion Performing shor rips You can call up he individual shor rips by using he 04 - Inroduce basic seings funcion. Various procedures have be se up for he differen engine conrol uni versions. You will find he measures and prerequisies for performing he shor rips of he individual engine conrol uni versions in he respecive workshop manuals. K-VK-36/rc/TI13_01gb.doc 31/

32 For inernal use only VOLKSWAGEN AG, Service Training, K-VK-36, Brieffach 1995 All righs reserved. Issued 09/99