Afternoon. I have a 1997 XK8 it runs great and there are NO lights on, on the dash. When I take it to the NYS inspection they plug in the inspection cable it try's to connect. It try's a few times and then says it can not connect to the car and it fails inspection. I have a Launch 129P scanner when I plug it in it try's a number of different and it fails on all of them? I then try a scan it scans with no problem i can check everything and clear errors if there are any. Anybody have any idea what what is the problem. I can not use the car at all because it fails inspection in NY. I have checked the OBDII plug it looked ok but I put in a new one to just make sure that was not the problem. Thank you in advanced to the help. George Re ( New York, Dutchess area.)

 

You can do some basic sanity checking. There are 2 fuses for the diagnostic connector, I believe. One is permanent 12V, the other is for switched 12V. Hard to believe a "sometimes" behavior would be fuse-related, but simple enough to check.

All you need for OBDII/inspection is the ISO-9141 bus, SCP and CAN are there but do not carry OBDII traffic.

Maybe start with another inspection station. Here they are all independent shops, so the equipment varies. Take your scanner with you to show them and persuade them to spend a bit more time.

Last, check the state laws for this inspection business. You may still be able to drive the car as you fix it, i.e.a failed report may give you more time on the road. There may be $ spent requirements, but some states allow for a waiver. Have you looked into the historic status? All of that varies by state...

 

Ditto on trying another inspection station.

I had that same issue last year where the station couldn't connect. After a moment of anxiety as I considered what would be involved in troubleshooting, I took it down the street to the next guy, and they had no issues.

 

Sorry for the delay in getting back on the form I was out of town. Thank you for all the help . I have checked the fuses all are good, I did replace the OBDII connector in the car just to make sure that was not the problem. I went to 3 stations all the same fail (No data Connection) . I have a launch scanner P129 it fails the data link but after it fails I can scan the car all works good i can look at any errors so do not know what else to do. So it is time to sell it , it is a 1997 XK8 with 80000 miles runs great, Real nice interior great top, good tires , only light error is the ABS but I know how to fix that but that won"t help me. Thank You George Re

 

If you have a bit more time to spare and you are comfortable messing with the wiring behind that plug, maybe temporarily simplifying the wiring will help.

As per: OBD-II_diagnostic_connector

All you need for OBDII (state inspection) is ISO-9141 (the yellow pair on that wikipedia page), battery and both grounds, The standard US-government OBDII is only available over the ISO-9141 wires. It is not available over CAN or SCP. To my knowledge, this is all the state inspection needs. So my suggestion is to disconnect all the other wires from that connector (and keep them isolated from each other). Maybe there is another connection pair that is wrong and confusing the scan tools (Some of the early cars have a funky airbag wiring on top of that). Temporarily setting them aside may help the tool focus on what it needs to get through this inspection. Hopefully the simplified wiring will correct all these errors, including your own tool. Just a thought.

At a later time, re-introduce the corresponding pairs of wires and check for error again. Start with the 2 wires for CAN, then move on to SCP, etc.

PS: The better answer is of course to dig out the official electrical manual on jagrepair.com and identify the wire colors to be triple sure. Again, you need to focus on the K-Line and L-Line of the ISO-9141-2 protocol and make sure each one is at the right spot in the connector.

 

Thank you for all the help I will try this today. Is there a difference between ISO 9141 and the ISO 9141-2 Question If this does not work any idea what I can ask for a 1997 XK8 runs great and looks good. any help work be appreciated. Will update this form after i try this.. Thank You George Re

 

I am still having a problem getting the inspection done here in NY. I have replaced the (DCL/OBDII connector, checked that the battery is fully charged, there are no error codes, ( the ABS light is on but I know how to fix it just have not gotten to it) , in one of the post s someone said I should try to make a temporary cable with only the power(pin 16) two grounds(4,5)and the K and L lines (7and 15) I did make it. Nothing works at all scanner nor the inspection station can connect. Have checked all the fuses all good. Do not know what to do from here. If anyone has any idea please let me know we really love the car and hate to have to get rid of it. Thanks again for all your help this is a great group... thks George

 

Are you working directly off the wiring on the back of the Jaguar diagnostic connector, or are you plugging in some sort of adapter with custom wiring?

At this point, you might be better off double checking the existing Jaguar connector in case someone messed with it before.

The electrical diagram is here: Jaguar 1997 Electrical Guide

On figure 19.1, you can see the details of the wiring of the diagnostic connector (right edge of the page). You definitely need the bottom section, pins 15 and 7 carry OBDII over the serial data link ISO-9141-2:




You need the top section, too (Pin 16 is Battery+, Pin 9 is switched Battery +, Pin 8 and 9 are switched ground):



Coloring is listed in the manual, too:


PS: Confusingly, the diagram above refers to the ISO-9141-2 lines by color. Functionally, the protocol refers to a "K" line and an "L" line. The functional "K" line is pin 7 (SEVEN, ORANGE wire). It idles high (12V) and has a resistance to battery of 510 Ohm (should be easy to test). Make sure these wires are not reversed.

 

Thank for the reply. I will be back at the car over the weekend and will check. I have checked the wires on the DCL/OBDII connector and are correct. In you r msg you said pind 1 nd 8 switch voltage did you mean 1 and 9 . I did make up a cable with just the 16,4,5,7,15 wires it did not work at all. will update you as soon as i get to the car. Thanks George

 

I updated the Battery/Ground description above.

 

Hi..I got to the car today. I checked all the wires on the DCL they are in the correct order. . I did make a custom cable with Just the basic wires needed,4,5,7,8,9 15,16 . Still does not work, will not connect....I am out of ideas as to what to do. It is a shame because the car is so nice and runs great but can not get it to pass inspection. SO I guess it time for it to go any idea what I can get for it? or just scarp metal? any ideas please let me know. Thank You for all your help. George Re

 

At the risk of being labeled a heretic, I would suggest taking your car to a Jaguar dealer or a good independent mechanic before resorting to selling the car.

 

Were you able to test this?

 

Hi sorry for the delay but was moving and just could not check it. Here is the update I looked at the female DCL connector again all looked OK But I ordered and other connector and installed it yesterday. My scanner now works OK it comes up with not ready which i knew because the battery was off of a while the code was P1000. I will have to drive the car for a while to get it to come ready then I will bring it to the inspection station and hopefully it will pass. Thank you for all you help on this and to the other member for there help. Asa soon as i can get it ready and inspected I will let you know. Thanks George

 

Just a update the car now shows ready took for inspection and passed with no problems. I want to thank everyone for all the help on getting this fixed. Now on to my next problem and it is the ABS light is on.

 

I cringe every time a need an inspection in NY on my '99 X-100. I have a Scan Gauge plugged in all the time. Other than supplying a better temperature reading, air intake temp, etc, I am able to check and clear unwanted reduced power/ and occasional check engine light. Yes, I've tried to hunt down cause with little results. Only does so on occasion. Light will pop on; oh its Tuesday. Little damp outside, little cold. Most annoying was just replacement of air filter. My cat runs fine. Great on fuel. I just clear codes and go on enjoying the drive. NYSI time, history is clear. NYSI passed. If another station does not help, try my method. If neither work, you can place an appeal with the state for an emission exemption. State will consider on an older vehicle if repair is too evasive and the vehicle is clearly not fogging the road as you drive. Other than that. Age exemption is not too far off. Good luck

 

At risk of sounding ignorant, I must ask, what is the female DCL connector ? I've been having similar connection problems with my OBDII scanner.

TIA

 

It is actually DLC, Data Link Connector, which is the OBD connector under the dash.

 

If a car fails NYS inspections a good choice for keeping the car is to register it in another state that does not require inspections such as Florida