I recently purchased a solid 1996 XJ6 and am thrilled to be a first time Jag owner! However my excitement has been dampened some as after a short time the check engine light appeared. Upon scanning the codes there are 3 of them:
P1193
P0158
P0138
I am looking for some help on what these codes are and how I might be able to clear these codes once and for all.

Thanks in advance!

 

Googling Gave me this:

Jaguar XJ range 96/97 Fuel, Emission Control and Engine Management Part1

Heated Oxygen Sensors – P1193
Model:
Jaguar XJ Range 1996, 1997
Complaint:
Fault code P1193 will most likely be set due to a H02S heater open circuit in the downstream sensor.
Remedy:
Switch off engine.
Check harness and connector condition and reliability, if a fault occurs then repair and go to step 7 of the test below.
Disconnect both downstream sensors and go to step 1 of the test below if no fault is found.
Test:
Ensure that each upstream sensor has a heater resistance between 5.3 and 6.7 Ohms. If this gives a positive result then go to step 2. If the limits are incorrect then replace the sensors, re-connect the harness and go to step 7.
Check harness continuity PI 126/003 is correctly wired to PI 127/003. If this gives positive results switch off the engine and go to step 3. If the circuit is open then find and repair the fault, re-connect the harness and go to step 7.
Check harness continuity PI 126/001 is correctly wired to PI 104/004. If this gives a positive result then go to step 4. If the circuit is open then find and repair the fault, re-connect the harness and go to step 7.
Check harness continuity PI 126/004 is correctly wired to RS 006/008. If this gives a positive result then go to step 5. If the circuit is open then find and repair the fault, re-connect the harness and go to step 7.
Check harness continuity PI 127/004 is correctly wired to RS 006/008. If this gives a positive result then go to step 6. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 7.
Check harness insulation PI 126/003 will complete a circuit to ground. If this gives a positive result then reconnect the harness and go to step 7. If it short circuits then find and repair the fault, re-connect the harness and go to step 7.
Clear the fault. Then in order to check if the fault code has been cleared perform the service drive cycle. If this gives a positive result then stop. If the fault is still present then go to step 8.
Repeat the diagnostic procedure. If this now omits a positive result then stop.
When testing
do not
test the resistance between sensor pins 3 and 4 as the generated current can damage the platinum electrodes.


Heated Oxygen Sensors – P0138/P0158
Model:
Jaguar XJ Range 1996, 1997
Complaint:
Fault code P0138/P0158 will most likely be set due to a H02S high voltage fault in the downstream sensor.
Remedy:
Switch off engine.
Check harness and connector condition and reliability, if a fault occurs then repair and go to step 11 of the test below.
If no fault is found then disconnect both downstream sensors and go to step 1 of the test below.
Test:
Check harness continuity PI 126/002 is correctly wired to PI 105/016. If this gives a positive result then go to step 2. If the circuit is open then find and repair the wiring fault, re-connect harness and go to step 11.
Check harness continuity PI 126/001 is correctly wired to PI 105/008. If this gives a positive result then go to step 3. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 11.
Check harness continuity PI 127/002 is correctly wired to PI 105/018. If this gives a positive result then go to step 4. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 11.
Check harness continuity PI 127/001 is correctly wired to PI 105/008. If this gives a positive result then go to step 5. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 11.
Ensure the insulation on the harness between the signal wires and Vbatt is working correctly. If this gives a positive result then go to step 6. If it short circuits then find and repair the wiring fault, re-connect the harness and go to step 11.
Check harness continuity PI 126/004 is correctly wired to RS 006/008. If this gives a positive result then go to step 7. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 11.
Check harness continuity PI 126/003 is correctly wired to PI 104/004. If this gives a positive result then go to step 8. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 11.
Check harness continuity PI 127/004 is correctly wired to RS 006/008. If this gives a positive result then go to step 9. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 11.
Check harness continuity PI 127/003 is correctly wired to PI 104/004. If this gives a positive result then go to step 10. If the circuit is open then find and repair the wiring fault, re-connect the harness and go to step 11.
If the continuity checks are positive then replace the sensors and re-connect them. If this now gives a positive result go to step 11.
In order to check if the fault code has been cleared perform the service drive cycle. If this gives a positive result then stop. If the fault is still present then go to step 12.
Repeat the diagnostic procedure. If this now omits a positive result then stop.
When testing
do not
test the resistance between sensor pins 3 and 4 as the generated current can damage the platinum electrodes.

 

Not a big deal. If you have a high miles Jaguar, its time to replace O2 sensors anyway. The good thing is you can find cheap O&M on ebay. I bough one several years ago and it cost over $150.00. You can get the same one for round $50.00. Any exhaust shop can replace the O2s for you for reasonable price. Be caution, the is a good chance that the O2 sensors will shear from the exhaust pipe. The O2 sensor body is made out of copper. You need to let the exhaust shop that if they break it they fix it .

hers is a link for $61.00

 

So, I just finished replacing both downstream O2 sensors and tried to start the engine and it won't turn over at all even though all the lights and fans come on. Any clue as to what is going on?

 

Do the lights go out when you attempt to crank it?
If so, that would indicate a poor connection somewhere - battery posts or earths somewhere. One that makes a circuit for small current flow, but is a no-go when you ask it to flow some serious current.
You can work your way through some of these...but I believe most are crank-but-won't-start but there are a handful of "won't-crank's" in there:
https://www.jaguarforums.com/forum/x...21/#post998822


Naturally, make a good second check around all areas where you performed service, make sure you haven't knocked a wire loose or something. Also check that you haven't blown a fuse. But also be prepared to accept that it may be a totally unrelated failure.

 

You didn't drop the car off the jacks hard, did you?

 

That's good advice aholbro1.

Another possibility could be the Park-Neutral switch. It might be worth trying to start the car in Neutral or wiggling the lever in Park to see if that makes a difference.

Just thinking out loud about wiring that could have been disturbed:

Battery power connection on the bulkhead?
Starter wiring?
Engine ground strap?

Is there a relay or fuse in the starter or body processor module circuit that could have been disturbed? The starter relay is on the left side of the engine bay near the air cleaner box....

One possible unrelated fault could be a weak battery - it might be worth measuring the voltage at the battery terminals while attempting to crank.

Cheers,

Don

 

LOL!

Ross, will the lights and fans come on if the inertia switch has been tripped? If you get two correct inertia switch diagnoses in a row I'll eat my hat!

Don

 

There is a possibility that the car was let down hard, (I guess) as we had it up and down several times. Also, we pushed it in and out of the driveway to rearrange cars. I have a Ford van that did the exact same thing and the only problem is that you MUST use the key fab to unlock the doors in order to start the engine. I think this is an anti-theft interlock. When we first bought the van shorting the starter did the trick before we learned about the key fab. Any chance there is something similar going on? Thanks all!

 

Hi alpilgrim,

The reason Ross asked if the car might have been let down hard from the jack is that he once tripped the inertia switch on his car by doing that. It would certainly be worth checking your inertia switch to be sure it hasn't been tripped, but I think all electric power to the lights and fans would be disconnected if the inertia switch were tripped, since part of its reason for existing is to prevent a fire caused by an electric spark igniting fuel vapors after a collision.

I think that on the X300 the inertia switch is mounted in the right hand footwell near the A-pillar or forward outer corner of the footwell behind the scuttle trim and carpeting. There is a button on top of the switch that IIRC pops up when an impact is sensed. To reset the switch, you just press the button back down till it latches.

If I've made any errors in the above, hopefully others will provide corrections.

Please keep us informed, alpilgrim!

Cheers,

Don

 

Yeah, I think that all circuits are dead if that happened, but I am not sure. Just wondering....

 

I found the "no start" issue to be the starter solenoid wire connector next to both O2 sensors at the rear of the engine compartment. It had come loose and just re seating the wire connector solved the problem!
Thanks all!
Alan