Hey guys like it says on the title i need help trying to find out what's wrong with my car. For some reason it shows a gear box fault. but when i connect it to the computer, it does not give me any numbers or shows no problems. I dont know know what else to do. any suggestions?? thanks

cars problem:
when it switches from 3rd to 4th gear it seems like it shifts again to 5th than immediately goes back to 4th.

2001 Jaguar S-type 5r55n tranny v6

 

A generic OBDII scanner might not detect transmission codes but they are in the PTEC (or there might not be any codes).
A trans shop might have the diagnostics to help???

WDS, IDS, AutoEnginuity, etc. should read the module.

bob gauff

 

There is no separate autobox module in that car. The PCM (aka ECM - yes, it's the kind known as a PTEC) does both engine and trans.

Any generic OBD tool SHOULD read whatever codes are present. However, some are faulty (badly programmed or some such), so I'd try a different one.

Many times an autobox "fault" turns out to be either a false code (see the TSBs - the PCM would need reflashing) or due to another problem usually one earlier in the powertrain (i.e. the engine). But you need the codes

 

Hey guys its been a while and i am still having a problem. i took the car to a shop which had 2 differant Computers and none read the codes for the gearbox. now i did get these codes and did research on them.

Code-
P-0420 - something to do with the Cat
p-1572- Brake switch circuit

Ive read in these forums that p-1572 is not just for brakes. it also has to do with "upshifting when staying on". which is the issue with my car as i stated above. my car goes 1st through 3rd gear with ease. than goes to 4th and than to 5th, and at times will go back to 4th. can this problem be a issue from the p-1572? and if so what parts should i buy?

thank you guys!!!!!! you guys have been a great help through the years with my Jaguar!

 

Please purchase the JTIS from EBay for $10. These cars are complex and you will spend a ton of money shooting in the dark like your doing now.
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Read the proper code meanings from the codes PDF in JTIS (& in the FAQs).

 

I am having the same experience with my transmission. First three gears perform as per the book. The shift up to 4th is a bit harsh, jumps to 5th back to 4th and the TCC seems to have a mind of it's own until well into the cruise. I'm brining the car to a transmission specialist tomorrow so that he can play with the car and call around his colleagues about the issue. He's already installed a new 4-3 preselect spring which cured the "no 5th gear" fault, but the next day this "gearbox fault" and 4-5-4 shift pattern showed up. It also takes a lot of throttle to induce a downshift, too. If you hear something, please let me know, and I will of course reciprocate. Gr. Steve

 

I had a similar problem and adjusting shifter linkage cleared the problem. Just check if when in drive , the switch on a tranny is fully engaged. No presure or pull on a swich. Hope this my help J.

 

Sorry for the slow update. We concluded the last component that could be changed without pulling the 'box was the solenoid pack. This was duely changed out and since then the 'box works fine. We were not able to conclude why the pack had failed, though, it is probably a consequence of the 4-3 selector spring failure. The spring supplier did mention that replacing both spring and solenoid pack was usual. I tried to go the simple route of changing one component at a time, also trying to save the 350 Euro price tag on the pack as other reports suggested just replacing the spring was sufficient...

 

Thanks for the follow-up. Sounds like you were a little unlucky but at least it's fixed!