Hello,
I've had this 2002 S Type 3.0 base car for about 3 weeks and have been working through the problems it has. I have replaced the battery, front right hub and abs sensor, and transmission fluid (not filter). I am using the Cen-Tech 60794 (OBD2/EOBD/ABS) from Harbor Freight to read the codes. I have no DTC or pending codes. For abs I have C1145, C1234, C1095, C1805, and U1262 before driving the car. The car starts right up and has a loud buzzing sound. I'm guessing it is coming from the transmission - it is very difficult to determine where it is coming from. I took off the drive belt and with just the engine running the sound is still there. The car backs out of the driveway but when placed in "D" (non sport mode) the car starts forward with decent power and at about 15 - 20 mph it shifts very hard but then shifts very softly into 2nd I suppose at about 25 - 30 and as I come up on 40 or so it sometime is a bit hard but many times is smooth. It is here mostly that it seems to start slipping but I have not pushed much past here. I can drive around for about 8 to 10 minutes (the loud buzzing sound continues but gets lower in intensity after about 10 minutes or so. Sometimes almost goes away.) After either reaching 40mph or the slipping starts - the slipping gets worse and worse and I can barely get it home. When home, if I check the codes I have 3 instead of 5. C1145, C1234 and C1095. I also can smell transmission fluid like it is hot or burning. After sitting for about 5 -10 minutes I can drive it again with the same symptoms as when I started. Today on the test drive after I returned home I put the car in sport mode and I was able to drive for probably another 30 - 40 minutes before slipping started. Sport mode increased the drive time considerably.

I will attack the front abs sensor again tomorrow to see if I can resolve it but the transmission issue I am not sure about. Would changing the fluid and filter be of any value? Does this sound like a problem that could be repairable (valve/solenoid) or transmission just needs replacing? Thank you, Jerry.

 

The 'buzzing' sound could be coming from the torque converter.

Is the gearbox fluid level correct?

 

Thanks for the reply. I drained it using the plug bolt on the bottom of pan. I filled it with a couple quarts then started filling it slowly watching for it to just trickle out. The car was running. I then closed it up with the center plug (screw). I have one of those infrared temperature gauges but i couldn't find it at the time. My driveway and street is slightly inclined ... how critical is it that the car be level and the temperature that you fill the transmission at be exact? I am not at a crazy angle but probably not perfect.

 

It is best to be on level ground if possible. You have the early model with the Ford trans. Seen a lot of torque converter issues with these, noisy, or throwing a code. However, some I've come across will have a slight buzzing noise, but car drives fine. Try to put the car on level ground if possible. It may be that it's time for a rebuild, if it's the one in your signature that has 188k on the clock.

When you put it the trans in sport mode, it changes the shift pattern, reducing the time it takes to shift from one gear to the next. Since your in a Jag, they want it nice and smooth, so you don't notice that it's shifting, but this causes more wear on the clutch packs inside because they are basically making contact longer to allow a smoother shift. For guys who put in shift kits, or modify the valve body to allow quicker more noticeable shifts, the length of time the clutch packs making contact is less, giving you a firmer shift.

Hope you were able to follow that, but given the amount of miles, and I'm assuming I've trans hasn't been removed for rebuild, it might be due for one. What did the old fluid look like? Did it smell burnt? Did you see and metal shavings in the oil? Any warnings on the dash?

 

Oh brother.........

 

It is critical that the vehicle be level and that the fluid be at the correct temperature when the level is checked.

If the temperature is lower, the level appears higher. If the vehicle is pitched at an angle, even a slight angle, the level may appear correct, but it is not.

 

Thanks everyone for replies. I have found a safe way to ensure car will be level and have a ir thermometer. I will recheck fluid level using proper procedures.

When i bought car the previous owner said that about 4 years ago he had the transmission rebuilt. He said the car ran fine for about two years. He then started having problems. He didn't say what problems. He took the car to a friend and he did some work but car stopped running about two weeks later and it has sat in place until now. Now is about two years from when it last stopped. I bought it with intention to put a transmission in it but thought i had nothing to lose by tinkering with it. I changed the transmission fluid (fluid was dark) by draining through plug. Car would drive down the street but was slamming into gear and trans was slipping like crazy. I borrowed a scanner that has can and i found codes that said front right sensor was bad. Front right sensor was badly damaged (stranded wire was exposed and i suspect shorting against body of car). I discovered that bearing was shot too so i replaced them both. Front sensor errors are still being reported but car smoothed out and i can drive it around like i mentioned in previous post. Hard shift from 1st to 2nd sometimes goes away sometimes comes back. One more thing. Before changing front sensor car would not go over 40mph. After changing sensor i could go over 45mph with no problems. Don't know if there is an upper limit - i am driving in neighborhood. I suspect the exposed wire caused a short which put the car in limp mode. Replacing the sensor released the limp mode.

 

I have been trying to resolve all other issues then concentrate on transmission problems. The error codes continue to point to the front right wheel sensor. I found that the replacement wheel sensor that i got from wrecking yard did not fit exactly but another one that i had gotten did fit perfectly. It positively and correctly latches (with clip) into place. I checked resistance from the abs connector and all 4 sensors showed about 43 ohms. Consistent and very close. I continue to get codes that show front right sensor???

Questions
1) Do these codes affect the operation of the transmission?'
2) Do these errors self clear or do they have to be cleared by scanner? (My scanner either cannot clear them or a problem is still there.)
3) Is it possible that the abs electronic board sustained some damage from the exposed stranded wire and is somehow defective? Maybe this is why i cannot clear the codes indicating a problem with the front right speed sensor.
4) Is there some driving sequence that must happen before codes can be cleared?

I'm trying to determine if i still have a problem with the front right speed sensor or the electronic board on the abs pump. And in addition, if this problem is affecting the diagnosis of the transmission problem.

I forgot to add this to the previous post on transmission. When driving the car from a cold start i can always tell that the transmission is about to start slipping because i will get a strong smell in cabin like transmission fluid is hot or burning. Slipping starts very soon after this.

Thanks, Jerry.

 

This morning i drained the transmission fluid via the drain plug and refilled using all the documented steps. My estimate is i was half a quart low. I drove the car and the buzzing noise was about 80 percent gone and sometimes it completely went away. For the most part it was there but much less pronounced. The hard shifting was greatly dimished - so much so that i would say it is acceptable. The shifting was very smooth. But as before, when i reached about 20 minutes of driving in the neighborhood (driving less than 40 mph) the slipping started and signaled me to head for home. Whatever is happening it must really be affected by the transmission/transmission fluid heating up.

 

I waited till now to go out and try car again to see how it would respond under a heavier throttle. Just trying to get another data point. When i started car up the buzzing noise was virtually gone and the car performed as if nothing was wrong with it after about a mile the buzzing noise maybe got a little louder but was much quieter than yesterday. I tried putting the pedal almost to the floor and car accelerated as expected. I did this several times and each time it performed correctly. This was only perhaps starting at 15mph up to 45 - 50 as i am still in the neighborhood. Then as before, it started slipping and i headed for home. I'm still trying to determine if this is something i can fix or do i need a replacement transmission.

 

I had another thought on this but maybe i am way off. Is it possible i am going into limp mode but don't realize it? It is consistently at 4 - 5 miles of driving or 20 minutes and the car starts slipping. It is like clockwork. It seems that you just turn the car off for a bit and the whole cycle repeats. I have no codes other than the ones mentioned and i have ordered a abs electronic board to replace mine. The codes i have seem to be related to the abs not transmission. (C1095, C1234, C1145, C1805, U1262)
Thanks, Jerry.

 

I went out to check condition of throttle position sensor and found that it was loose and could freely rotate around shaft. I have no idea why someone was messing with this but i am going to check its adjustment and position it back where it belongs.

 

Installed tps and tightened down. Still have same 5 codes as shown above. Car drove for about 20 minutes again and started slipping. Could smell hot/burning transmission fluid so brought home and parked it. Drove about 7 miles this time around neighborhood. Waiting for abs board to put in and see if any symptoms change.

 

I know the C1095 code is for the pump circuit in the control module. As for the other codes, C1234 is for Right front wheel speed sensor, C1145 is also for Right Front wheel speed sensor, C1805 means ABS/ TCCM mismatch with PCM. I've seen the C1095 code come up a lot, specially with the XJ 308, and early XK's. I have seen it with the S-type a few times, but generally they are pretty good. Since you have the C1805 code logged as well, most likely you have a faulty ABS module. Still doesn't mean you don't have a fault with the speed sensor. Have you tried swapping the sensor lead to the Left side and see if the fault moves there? If it doesn't, then because of the other codes logged, it looks like its pointing to the ABS module. Just for safe measure, check all your fuses and make sure they are all good.




U1262 has to do with Driver Seat control module, either there is a network failure or the driver seat control module has failed.

 

In the S-Type codes PDFs I see a different meaning for U1262, relating to the audio unit.

Kinda wondering where you found it was about the seat module?

 

+1 on U1262 being related to the audio unit. Seems to show up as a common code in Jag level diagnostic scanners...

 

Thank you to everyone that has responded. I am out of the game for a few days with kidney stones again. I would like to ask what code scanner are most of you using. I think mine is not reading all the code and spinning me in circles. And will transmission codes show up with just a generic obdii scanner. A recap, i changed the abs control board and cleared the codes. No speed sensor codes have reappeared. I cleaned throttle assembly, cleanded the engine and body grounds, replaced the battery, replaced oil pan gasket, IAT orings with green ones, fuel filter, and air filter. I took car to transmission shop and he said that he saw code p0735 ( could be wrong, this is from memory) and said he could rebuild it for $3,500. I just happened to see a blurp about a 4 3 spring and it had the same code and slipping so i ordered the spring and dropped the valve body. Somebody had put two spring in the valve body that we not even touching the valve so the symptoms matched the cause. The separater plate gasket was stuck to the valve body so i took everything over to a transmission guy and he said that he would clean and replace the gasket and check everything out for me. He also showed me that someone had installed a shift kit in the valve body as well. When i get valve body back i will install it and see where i am with the transmission problem. Does any one know if i have to prime the transmission before starting car?

Since clearing the codes i have not seen a single code saying anything is wrong. ????

 

Looks like you have the 5R55N trans. It & engine are operated by the PCM so any code reader should work (some nevertheless do not as they are faulty). Look up any codes in the jag docs so you get the right meaning and all the possible causes.

 

I got the valve body back in the buzzing sound disappeared. I hard reset computer and car drove for over an hour around the neighborhood without incident. When i tried to go on the freeway i got a "transmission fault" and it started slipping so i just slowed down and drove car home. As long as i stay under 45mph or so car drives and operates perfectly. I am in "sport mode" too.
I tried adjusting the intermediate and overdrive bands and drove car again. I could get over 55mph a few times then it appears to not be able to change from 4th gear i suppose. It also generates a gear 4 and gear 5 code (74 and 75 i believe).

I know the overdrive adjustment is correct because i had easy access to it. Does anyone have a method of accurately measuring the 120 in/lbs on the intermediate adjuster with transmission still in car? It is difficult to access that stud.

 

Looks like you have to remove the switch/bracket to gain access to the stud. No way around it.