b"VolkswagencoolingsystemscanseemaThecoolingsystememploysavarietyofstrategies,buttwoofthose bit like a maze at times, with hoses teeingstrategiesweremostpertinenttothisdiagnosis:EngineWarmingand R\x03RI\x03HDFK\x03RWKHU\x03DQG\x03URXWLQJ\x03HYHU\\\x03ZKLFK\x03 IndependentHeating.EngineWarmingtakesplaceduringacoldstart. ZD\\\x03XQGHU\x03WKH\x03KRRG\x11\x037KH\x03RZ\x03GLDJUDP\x03LQ\x03 7KH\x03URWDU\\\x03VOLGH\x03YDOYHV\x03LQ\x03WKH\x03WHPSHUDWXUH\x03DFWXDWRU\x03UHVWULFW\x03FRRODQW\x03RZ\x0f\x03serviceinformationfurthercementstheallowing the engine to reach closed loop operating temperatures as quickly feeling of being lost in a maze full of twistsaspossible.Thiscontributestoloweredemissionsandincreasedfuel and turns and dead ends.HFRQRP\\\x11\x037KH\x03FRRODQW\x03VKXW\x10R\x03YDOYHV\x03DUH\x03FORVHG\x03GXULQJ\x03WKH\x03ZDUPLQJ\x03SKDVH\x03DV\x03 ZHOO\x11\x03 $IWHU\x03 VXFLHQW\x03 KHDWLQJ\x03 RI\x03 WKH\x03 HQJLQH\x0f\x03 WKH\x03 WUDQVPLVVLRQ\x03 FRRODQW\x03ThismazeismadeevenmorecomplexVKXW\x10R\x03YDOYH\x03RSHQV\x0f\x03DQG\x03WKH\x03URWDU\\\x03VOLGHV\x03PRYH\x03WR\x03DOORZ\x03IXOO\x03RZ\x03WKURXJK\x03The cooling system employs a variety of strategies, but two of thosestrategies were most pertinent to this$FWLYDWH\x03FRROLQJ\x03V\\VWHP\x03FRPSRQHQWV\x03XVLQJ\x03WKH\x03 V\\VWHP\x03 FRPSRQHQWV\x11\x03 $W\x03 WKLV\x03 SRLQW\x0f\x03 LW\x03 ZDV\x03 WLPH\x03the radiator.$FWLYDWH\x03FRROLQJ\x03V\\VWHP\x03FRPSRQHQWV\x03XVLQJ\x03WKH\x03 V\\VWHP\x03 FRPSRQHQWV\x11\x03 $W\x03 WKLV\x03 SRLQW\x0f\x03 LW\x03 ZDV\x03 WLPH\x03 There are two codes which can be set for the N82$IWHU\x03VXFFHVVIXOO\\\x03EOHHGLQJ\x03WKH\x03FRROLQJ\x03V\\VWHP\x03DQG\x03EHFDXVH\x03 WKH\x03 RZ\x03 FDQ\x03 PRUSK\x03 GHSHQGLQJ\x03 diagnosis: Engine Warming and Independent Heating. Engine Warming takes place during a cold start.scan tools Output Functions, including electrictocheckthecoolingsystemforrestrictionswith scan tools Output Functions, including electrictocheckthecoolingsystemforrestrictionswithYDOYH\x1d\x03 3\x14\x1b\x1b\x1c\x03 &RRODQW\x03 6KXW\x102\x03 9DOYH\x03 VKRUW\x03 WR\x03 LQVWDOOLQJ\x03 D\x03 QHZ\x03 FDELQ\x03 DLU\x03 OWHU\x0f\x03 WKH\x03 HQJLQH\x03 ZDV\x03onenginetemperatureandoperatingThe rotary slide valves in the temperature actuator restrict coolant flow, allowing the engine to reachFRRODQW\x03SXPSV\x03DQG\x03FRRODQW\x03VKXWR\x03YDOYHV\x11\x03 athermalimager.Thismethodisslightlymore The Independent Heating strategy kicks in when a heat setting is selectedFRRODQW\x03SXPSV\x03DQG\x03FRRODQW\x03VKXWR\x03YDOYHV\x11\x03 athermalimager.ThismethodisslightlymoreJURXQG\x12RSHQ\x03 FLUFXLW\x1e\x03 DQG\x03 3\x14\x1b\x1b\x1b\x03 &RRODQW\x03 6KXW\x102\x03 startedandwithinminutestherewasexcellent closed loop operating temperatures as quickly as possible. This contributes to lowered emissions andRuntheenginetemperaturemanagementinvolvedthanthescantoolchecks,butitisstill FRQGLWLRQV\x11\x03 6HUYLFH\x03 LQIRUPDWLRQ\x03 LV\x03 HDVLO\\\x03 E\\\x03 WKH\x03 GULYHU\x11\x03 ,Q\x03 WKLV\x03 VFHQDULR\x03 WKH\x03 1\x1b\x15\x03 FRRODQW\x03 VKXWR\x03 YDOYH\x03 ZLOO\x03 EH\x03 Runtheenginetemperaturemanagementinvolvedthanthescantoolchecks,butitisstillValve short circuit to B+. No faults were present onheatoutputfromthevents.Doublecheckingfor Cooling Systemincreased fuel economy. The coolant shut-off valves are closed during the warming phase as well. AfterDFWXDWRU\x03%DVLF\x036HWWLQJ\x0f\x03ZKLFK\x03UXQV\x03WKH\x03URWDU\\\x03 non-invasive.OHDNV\x03DQG\x03D\x03SRVW\x03VFDQ\x03RI\x03WKH\x03YHKLFOH\x03FRQUPHG\x03WKHUH\x03 forgotten,butisjustwhatwasneededinsufficientG\x0f\x03DOORofQJ\x03FRRODQW\x03RZ\x03WKURXJK\x03WKH\x03KHDWHU\x03FRUH\x03WR\x03PHHW\x03WKH\x03FDELQ y slides moveDFWXDWRU\x03%DVLF\x036HWWLQJ\x0f\x03ZKLFK\x03UXQV\x03WKH\x03URWDU\\\x03 non-invasive.the GTI because the electrical circuits were OK. The RSHQH heating ZL the engine, the transmission coolant shut-off valve opens, and the rotar \x03 slide valves through their various positions.)ORZ\x03'LDJUDP slide valves through their various positions. failure was mechanical and therefore not detectablewerenoissuescreatedduringtherepair.The this case to gain a clear understanding ofto allow full flow through the radiator. 0RQLWRU\x03FRRODQW\x03WHPS\x03VHQVRUV\x0f\x03VKXWR\x03YDOYHV\x0f\x03 Everything looked normal with the thermal camera heating demands. The electric coolant recirculation pump may also be0RQLWRU\x03FRRODQW\x03WHPS\x03VHQVRUV\x0f\x03VKXWR\x03YDOYHV\x0f\x03 Everything looked normal with the thermal cameraE\\\x03WKH\x03(&0\x11 hatchback was released back to the owner, who was XQWLO\x03 UHDFKLQJ\x03 WKH\x03 1\x1b\x15\x03 FRRODQW\x03 VKXWR\x03 YDOYH\x11\x03the cooling system components and theorycommanded On.and coolant pumps through scan tool live data. XQWLO\x03 UHDFKLQJ\x03 WKH\x03 1\x1b\x15\x03 FRRODQW\x03 VKXWR\x03 YDOYH\x11\x03 veryhappytonothavetodrivetoworkwithhis and coolant pumps through scan tool live data.The Independent Heating strategy kicks in when a heat setting is selected by the driver. In this scenario/RFDWHG\x03EHKLQG\x03WKH\x03OHIW\x03DLU\x03JXLGH\x03SLSH\x0f\x03WKH\x03FRRODQW\x03of operation. the N82 coolant shutoff valve will be opened, allowing coolant flow through the heater core to meet theThebasicsettingswererunsuccessfully,andthe/RFDWHG\x03EHKLQG\x03WKH\x03OHIW\x03DLU\x03JXLGH\x03SLSH\x0f\x03WKH\x03FRRODQW\x03 $Q\x03 LPSRUWDQW\x03 VLGH\x03 QRWH\x03 LV\x03 WR\x03 FDUHIXOO\\\x03 LQVSHFW\x03 WKH\x03 thermal underwear, stocking cap and winter gloves YDOYH\x03LV\x03REVFXUHG\x03IURP\x03YLHZ\x0f\x03EXW\x03ZLWK\x03VRPH\x03HRUW\x03:LWK\x03 D\x03 FOHDU\x03 XQGHUVWDQGLQJ\x03 RI\x03 FRRODQW\x03 RZ\x03 DQG\x03 WKH\x03 GLHUHQW\x03 RSHUDWLQJ\x03 Thebasicsettingswererunsuccessfully,andtheYDOYH\x03LV\x03REVFXUHG\x03IURP\x03YLHZ\x0f\x03EXW\x03ZLWK\x03VRPH\x03HRUW\x03 connectors and wiring for coolant migration: coolanton any more. cabin heating demands. The electric coolant recirculation pump may also be commanded On.RXWSXW\x03 IXQFWLRQDO\x03 WHVWV\x03 DOO\x03 SDVVHG\x11\x03 /LYH\x03 VFDQ\x03 GDWD\x03 temperature readings were taken at both sides of RXWSXW\x03 IXQFWLRQDO\x03 WHVWV\x03 DOO\x03 SDVVHG\x11\x03 /LYH\x03 VFDQ\x03 GDWD\x03TheheartofthethermalmanagementsystemistheN493enginemodes of the thermal management system, it was time to create an actionshowed normally operating blend doors and coolingtemperature readings were taken at both sides ofleaking through a sensor or pump can wick into the SODQ\x03VWDUWLQJ\x03ZLWK\x03WKH\x03OHDVW\x03LQYDVLYH\x03WHVWV\x03UVW\x11\x037\\SLFDOO\\\x0f\x03WKH\x03EHVW\x03WHVWV\x03WR\x03 showed normally operating blend doors and cooling the valve. The inlet hose was warming up consistent:LWK\x03 SURGXFWLRQ\x03 TXRWDV\x03 DQG\x03 DW\x03 UDWH\x03 KRXUV\x03 DW\x03temperaturecontrolactuator,whichutilizestworotaryslidevalvestoWith a clear understanding of coolant flow and the different operating modes of the thermal manage- the valve. The inlet hose was warming up consistentwiring harness. If any contamination is found in the with the engine, but the outlet hose leading to thestake, there is a real temptation to load the parts with the engine, but the outlet hose leading to theconnector, the rest of the wiring back to the engine start with can be done with a scan tool from the front seat of the vehicle. heater core and the heater pipes was stagnant atcontrol module should also be inspected. GLUHFW\x03FRRODQW\x03RZ\x03DQG\x03KRXVHV\x03WKH\x03WRRWKHG\x03EHOW\x10GULYHQ\x03FRRODQW\x03SXPS\x03DQG\x03 ment system, it was time to create an action plan starting with the least invasive tests first. Typically, theheater core and the heater pipes was stagnant atcannon and replace the component with the highest thermostat wax capsule.best tests to start with can be done with a scan tool from the front seat of the vehicle. around60degrees;itappearedthatthecoolantfailure rate for any given problem, and that is likely $FWLRQ\x033ODQ\x033ULRULW\\\x03/LVW\x1d around60degrees;itappearedthatthecoolant Action Plan Priority List: VKXWR\x03YDOYH\x03ZDV\x03FORVHG\x0f\x03GHVSLWH\x03WKH\x03VFDQ\x03WRRO\x03GDWD\x03 With the new N82 valve installed the next step was towhathappenedwiththeunnecessaryheatercore Run the blend door calibration in Basic Settings to verify operation and confirm no fault codes set.VKXWR\x03YDOYH\x03ZDV\x03FORVHG\x0f\x03GHVSLWH\x03WKH\x03VFDQ\x03WRRO\x03GDWD\x035XQ\x03WKH\x03EOHQG\x03GRRU\x03FDOLEUDWLRQ\x03LQ\x03%DVLF\x036HWWLQJV\x03WR\x03YHULI\\\x03RSHUDWLRQ\x03 showing it was commanded open.bleed the cooling system. Volkswagen recommendsreplacement on this GTI. There is also an electric after-run coolant pump, a recirculation pump, andMonitor specified and actual values of the temperature doors in live data. showing it was commanded open. WZR\x03FRRODQW\x03VKXWR\x03YDOYHV\x03LQ\x03WKH\x03V\\VWHP\x11\x032QH\x03RI\x03WKH\x03VKXWR\x03YDOYHV\x03LV\x03RQ\x03WKH\x03 DQG\x03FRQUP\x03QR\x03IDXOW\x03FRGHV\x03VHW\x11\x030RQLWRU\x03VSHFLHG\x03DQG\x03DFWXDO\x03YDOXHV\x03RI\x03 The testing so far was clearly indicating a problemWKH\x03XVH\x03RI\x03D\x03YDFXXP\x03OO\x03WRRO\x03DIWHU\x03D\x03FRROLQJ\x03V\\VWHP\x03 6HDUFKLQJ\x03WKH\x03V\\PSWRP\x03RI\x03\x05QR\x03KHDW\x05\x03RQ\x03D\x03SRSXODU\x03the temperature doors in live data. The testing so far was clearly indicating a problemrepair.Therearemanyofthesetoolsavailable inlet side of the heater core, and the other is for the transmission cooler onwiththeN82valve. ThecommandwasthereforSDLG\x03\x05[\x05\x03GDWDEDVH\x03EURXJKW\x03EDFN\x03KXQGUHGV\x03RI\x03KLWV\x03IRU\x03withtheN82valve. Thecommandwasthereforeither as part of a coolant pressure tester set, or as it to be open and there were no fault codes for thea restricted heater core. This method of going after YHKLFOHV\x03HTXLSSHG\x03ZLWK\x03D\x03'6*\x03DXWRPDWLF\x03WUDQVPLVVLRQ\x11 it to be open and there were no fault codes for theD\x03 VWDQG\x10DORQH\x03 UHOOLQJ\x03 GHYLFH\x11\x03 $\x03 FDSDEOH\x03 VFDQ\x03 WRRO\x03 the low hanging fruit and replacing the most likely YDOYH\x0f\x03 VR\x03 D\x03 PHFKDQLFDO\x03 SUREOHP\x03 VHHPHG\x03 OLNHO\\\x11\x03 $\x03Sample Rate: 8.0 - VCDS YDOYH\x0f\x03 VR\x03 D\x03 PHFKDQLFDO\x03 SUREOHP\x03 VHHPHG\x03 OLNHO\\\x11\x03 $\x03 LV\x03DOVR\x03UHTXLUHG\x03ZKHQ\x03UHOOLQJ\x03WKH\x03V\\VWHP\x11\x037KHUH\x03LV\x03 cause of a given issue may work sometimes, but not Stop QHZ\x03FRRODQW\x03VKXWR\x03YDOYH\x03ZDV\x03RUGHUHG\x03\x03DQG\x03WKH\x03ROG\x03 D\x03 &RROLQJ\x03 6\\VWHP\x03 5HOOLQJ\x12%OHHGLQJ\x03 IXQFWLRQ\x03 WKDW\x03QHZ\x03FRRODQW\x03VKXWR\x03YDOYH\x03ZDV\x03RUGHUHG\x03\x03DQG\x03WKH\x03ROG\x03EngineEngine inlet Label File: 06K-907-425-V1.CLB Basic Settings valve was removed.needs to be run under the Guided Functions menu.RIWHQ\x03HQRXJK\x03WR\x03NHHS\x03FXVWRPHUV\x03KDSS\\\x03DQG\x03SURWV\x03LQ\x03output valve was removed.WKH\x03EODFN\x11\x03$\x03\x18\x13\x13\x03EDWWLQJ\x03DYHUDJH\x03PD\\\x03EH\x03RXWVWDQGLQJ\x03TemperatureIDE05231-Engine temperature management actuator Thisfunctionopenscoolantvalvesandmayrun $IWHU\x03GUDLQLQJ\x03WKH\x03FRRODQW\x0f\x03WKH\x03DLU\x03OWHU\x03KRXVLQJ\x03DQG\x03 in baseball, but it is a failing grade in the shop. control of$IWHU\x03GUDLQLQJ\x03WKH\x03FRRODQW\x0f\x03WKH\x03DLU\x03OWHU\x03KRXVLQJ\x03DQG\x03 electric pumps as well to aid in getting all the air out air guide pipe need to be removed to gain access air guide pipe need to be removed to gain accessRI\x03WKH\x03V\\VWHP\x11\x03&RQVXOW\x036HUYLFH\x03,QIRUPDWLRQ\x03IRU\x03DQ\\\x03 $\x03 WHFKQLFLDQ\x03 QHHGV\x03 WKH\x03 PLQGVHW\x03 RI\x03 D\x03 VQLSHURQH\x03the actuatorGo! Finished correctly Itothevalve.Fromthereitisastraightforward motor N493 Heater Pipes Thermal Imager tothevalve.FromthereitisastraightforwardTXHVWLRQV\x03UHODWHG\x03WR\x03UHOOLQJ\x03WKH\x03FRROLQJ\x03V\\VWHP\x11 shot one kill, or in automotive terms one part one Rotary slide 2 Heater Pipes Thermal Imager replacement with two spring clamps and two bolts. replacement with two spring clamps and two bolts.repair. Of course, some repairs require more than Show Measuring Data Done, Go Back Of course, caution is needed to not damage any of Of course, caution is needed to not damage any of6HOHFWLQJ\x03 WKH\x03 FRUUHFW\x03 FRRODQW\x03 LV\x03 DOVR\x03 FULWLFDO\x03 IRU\x03 one part, but operating with the sniper philosophy the myriad of other hoses and connectors that arequality and long-term repairs. Volkswagen has had the myriad of other hoses and connectors that arewillresultinacorrectdiagnosisratherthanan N493 Basic Setting W\\SLFDO\x03IRU\x03D\x039$*\x03HQJLQH\x03ED\\\x11\x03 several coolants over the past 20 years, starting with Supply toW\\SLFDO\x03IRU\x03D\x039$*\x03HQJLQH\x03ED\\\x11\x03 HGXFDWHG\x03 JXHVV\x11\x03 &RQWLQXHG\x03 WUDLQLQJ\x03 DQG\x03 VROLG\x03radiator Whenthenewvalvearrived,andaside-by-side*\x14\x14\x03DQG\x03WKH\x03ODWHVW\x03EHLQJ\x03*\x14\x16\x11\x036RPH\x03RI\x03WKHVH\x03FRRODQWV\x03 troubleshooting skills are required to keep up with Whenthenewvalvearrived,andaside-by-sidearebackwardscompatibleandcanbemixed,but comparisoncouldbemade,theissuewastheever-evolvingtechnologythattechniciansare VCDS comparisoncouldbemade,theissuewasclear.clear.Volkswagen does not recommend this practice as itfaced with every day. |The resting state of the new valve was open with Advanced Measuring Values The resting state of the new valve was open withshortens the life of the coolant. The theplungerretracted,buttheplungeronthe theplungerretracted,buttheplungeronthecorrectcoolanttypecanusuallybe Sample Rate: 1.3 Turbo! RULJLQDO\x03YDOYH\x03ZDV\x03IXOO\\\x03H[WHQGHG\x0f\x03LPSHGLQJ\x03WKH\x03RZ\x03RULJLQDO\x03YDOYH\x03ZDV\x03IXOO\\\x03H[WHQGHG\x0f\x03LPSHGLQJ\x03WKH\x03RZ\x03 found printed on the side of expansion ofcoolanttotheheatermatrix,androbbingthe ofcoolanttotheheatermatrix,androbbingthetank.Furtherdetailsregardingthe Group UDS requests passenger compartment of heat.passenger compartment of heat. GLHUHQW\x03FRRODQW\x03W\\SHV\x03DUH\x03FRYHUHG\x03LQ\x03Loc. Description Actual )XUWKHU\x03UHDGLQJ\x03RQ\x03WKH\x031\x1b\x15\x03FRRODQW\x03VKXWR\x03YDOYH\x03 7HFKQLFDO\x036HUYLFH\x03%XOOHWLQ\x03\x14\x1c\x10\x14\x1a\x10\x13\x14\x03\x03Back)XUWKHU\x03UHDGLQJ\x03RQ\x03WKH\x031\x1b\x15\x03FRRODQW\x03VKXWR\x03YDOYH\x03 IdentifyingandMixingVolkswagen providedaclearerunderstanding.Thevalvecan of theIDE. Coolant temperature 106 C providedaclearerunderstanding.Thevalvecan(QJLQH\x03&RRODQWV\x11\x03DOVR\x03 EH\x03 UHIHUUHG\x03 WR\x03 DV\x03 D\x03 &RRODQW\x03 %ORFNLQJ\x03 9DOYH\x0f\x03oilIDE. Coolant temperature at radiator outlet: actual. 22.9 C DOVR\x03 EH\x03 UHIHUUHG\x03 WR\x03 DV\x03 D\x03 &RRODQW\x03 %ORFNLQJ\x03 9DOYH\x0f\x03cooler which may be a more apt name (especially for this which may be a more apt name (especially for this$V\x03D\x03QDO\x03VWHS\x0f\x03EH\x03VXUH\x03WR\x03LQVSHFW\x03WKH\x03IDE. Coolant temperature at engine outlet: specifie. 106.5 C *7,\x0c\x11\x03 7KH\x03 YDOYH\x03 LV\x03 SUHVHQW\x03 RQ\x03 PXOWLSOH\x03 GLHUHQW\x03*7,\x0c\x11\x03 7KH\x03 YDOYH\x03 LV\x03 SUHVHQW\x03 RQ\x03 PXOWLSOH\x03 GLHUHQW\x03 FDELQ\x03DLU\x03OWHU\x03ZKHQ\x03GHDOLQJ\x03ZLWK\x03DQ\\\x03HQJLQHV\x03DFURVV\x039RONVZDJHQ\x03DQG\x03$XGL\x03PRGHOV\x03DQG\x03Belt drive IDE. Coolant shut-off valve Open HQJLQHV\x03DFURVV\x039RONVZDJHQ\x03DQG\x03$XGL\x03PRGHOV\x03DQG\x03 +9$&\x03FRPSODLQW\x11\x03$\x03GLUW\\\x03RU\x03UHVWULFWHG\x03IDE. Coolant circulation pump: activation 10.00 % PD\\\x03DOVR\x03EH\x03ODEHOHG\x03DV\x031\x17\x15\x15\x03&RRODQW\x036KXW\x102\x039DOYH\x03PD\\\x03DOVR\x03EH\x03ODEHOHG\x03DV\x031\x17\x15\x15\x03&RRODQW\x036KXW\x102\x039DOYH\x03 OWHU\x03ZLOO\x03OLPLW\x03DLURZ\x03IURP\x03WKH\x03YHQWV\x0f\x03GearCoolant pump &OLPDWURQLF\x11\x03 3RZHU\x03 WR\x03 WKH\x03 YDOYH\x03 LV\x03 VXSSOLHG\x03 IURP\x03&OLPDWURQLF\x11\x03 3RZHU\x03 WR\x03 WKH\x03 YDOYH\x03 LV\x03 VXSSOLHG\x03 IURP\x03 UHGXFH\x03ZLQGVKLHOG\x03GHIURVWHU\x03HFLHQF\\\x03worm RotaryIDE. Transmission coolant valve Open IXVH\x036%\x1a\x03LQ\x03WKH\x03XQGHU\x10KRRG\x03IXVH\x03EORFN\x11\x037KLV\x03IXVH\x03slide 1 Back heating,IXVH\x036%\x1a\x03LQ\x03WKH\x03XQGHU\x10KRRG\x03IXVH\x03EORFN\x11\x037KLV\x03IXVH\x03 and put undue stress on the blower IDE. Heater support pump: spec. value 65.11%is shared by eight other components including the turbochargeris shared by eight other components including thePRWRU\x11\x03$OVR\x0f\x03VHOHFW\x03D\x03TXDOLW\\\x03FDELQ\x03OWHU\x037UDQVPLVVLRQ\x03&RRODQW\x039DOYH\x11\x03*URXQG\x03VLGH\x03FRQWURO\x03RI\x03and gearbox 7UDQVPLVVLRQ\x03&RRODQW\x039DOYH\x11\x03*URXQG\x03VLGH\x03FRQWURO\x03RI\x03 IRU\x03 EHVW\x03 WPHQW\x03 DQG\x03 SHUIRUPDQFH\x0f\x03Back radiator Graph Log Save Done, Go Back WKH\x03VKXWR\x03YDOYH\x03LV\x03SURYLGHG\x03YLD\x03WKH\x03HQJLQH\x03FRQWURO\x03 making sure to use charcoal infused WKH\x03VKXWR\x03YDOYH\x03LV\x03SURYLGHG\x03YLD\x03WKH\x03HQJLQH\x03FRQWURO\x03N493 Temperature Control Actuator Cross Viewmodule. Understanding the design of a circuit willCabin Filtersmodule. Understanding the design of a circuit willOWHUV\x03ZKHQ\x03UHTXLUHG\x11(Image Courtesy Volkswagen) &RRODQW\x036HQVRUV\x03\x036KXW\x102\x039DOYHV\x03/LYH\x03'DWD New N82 Valve make testing that circuit a much easier endeavor.New N82 Valve make testing that circuit a much easier endeavor.31 8"