Hi Takeo,

What codes are now being triggered?

I just reviewed the DTC Summary for the P0706 you reported in your original post., and as M. Stojanovic previously posted, here is the definition:





It looks like your next steps should be to check the gear selector cable adjustment and to clean the electrical connectors at the transmission and check for any signs of damage to the wiring harness.

You can download the wiring schematics at the link below:

Jaguar X308 Electrical Guide 2001

Cheers,

Don

 

Thanks, DON !

My yesterday experinece was on her OLD TCM. I replaced what I think was D4 microswitch and she drove normally for a while.

I read what you sent to me and I think there maybe some wear on the large D disk, which could explain, woring properly, driving over a sewer lid and go into limp mode.

Alsom now, as soon as I even think of taking revers gear: limp mode, it is as if any mechanical shifting disturbance mes her act up.

Gear shift cable has not been touched in 21 years and I cannot reach it anyway, I will now check wear on the hole where the shift lever passes try the D disk and the central play in the disk as well.

Will also check for grounding ...

O will try to ake a picture to send you.

Thanks for your help,

Takeo.

 

Hi DON,

I am back. (again).

I took the shifter cover off, checked all contacts and microswitches and put the whole dmaned thing back together and went for a test drive.

Car drove normally for about 1 Km, shifted through all gears and then just fell out of 5th, so I drove on a bit and stopped for about half an hour (engine off), chatted with a neighbour.

Half hour chat, started engne again and drove off, shifted normally for, again about 1 Km and then fell out of 5th again and I drove home in 4th.

Here is a pic of the microswitches, the NEW switch is the one on the right (originally rivetted in but now held by 2 mini-screws and secured with a zip tie. It CANNOT move.

Same as yesterday.

What I am thinnkng of now might be a bad battery (new one, not even 1 year old). I measure only 10.8 or 11 V on the battery. I wonder if that would affect the TCM much. New alternator is also only 1 year old.

? ? ? ? ? I am a bit lost now ...

Nave a nice day,

Takeo.

 

Hi Takeo,

Whenever Limp Mode is triggered, there should also be one or more diagnostic trouble codes (DTCs) stored in the ECM and/or TCM. I was suggesting that you need to scan again to see what code or codes are currently being triggered. If it is still P0706, then the first step listed under Possible Causes is to check the cable adjustment. The other steps refer to the rotary switch, which is on the side of the transmission, not in the center console.

The cable adjustment is done by loosening the nut and adjusting the "L-shaped" end piece to change the effective length of the cable. See the three parts listed under Part 1 on this diagram:



The rotary switch is on the right side of the transmission. See the link M. Stovanovic provided in Post #19:



Cheers,

Don

 

11V on the battery is very low. Did you measure it when the engine was off, immediately after engine switch-off or after the car had sat overnight? What voltage do you have on the battery while the engine is running?

If the voltage is below 13V while the engine is running, then you have a problem with the alternator. This will cause all sorts of issues including transmission faults, restricted performance etc. A good alternator should keep the voltage in the system and on the battery at some 13.5 to 14.2 Volt.

Keeping the battery at around 11V will cause its accelerated sulfation and ruin it.

 

Hello,

Me again.

I have been checking all I could. I have doubts about the selector cable being un-adjusted.

The gearbox had a 100% overhaul 15,000 Km ago. And all worked perfect. (the gearbox insides are ALL 100% NEW).

Nothing repairs itself.

Been 2 days now that:

* Contact ON no fault messages except the orange engine icon, I clear that with my OBD (P 0706 as usual).
* Contact OFF and ON again : all is normal
* I drive 1 - 10 km and, all of a sudden, Gearbox Fault and switches to 4th gear but I can rev her up to 7,000
* Fuel consumption goes to 35 liters / 100 Km.

* Stop wherever I can
* Contact OFF
* Wait 10 minutes
* Contact ON
* All normal
* Everything ok, shifts all gears for the next 1-20 Km

And so on and so on ...

(I have the impression that I have less problems when gearbox is warm ????).

Takeo.

 

I assume that you mean is that all the typical wear components were replaced during the overhaul (frictions, seals, possibly the A-drum, etc.) It would be very unusual for all the gears, shafts, drums and other hard components to be replaced during an overhaul, not to mention very, very expensive.

It is possible that your rotary switch has a temperature-dependent malfunction. Of course, the same is true of your TCM. It is possible to test for this by taping a bag of ice on the component, or spray it with a product like Freeze Off, to see if the malfunction lasts longer. Or, use a heat-gun or hair dryer to warm the rotary switch or TCM immediately before taking a test drive to see if things are improved.

Have you cleaned the electrical connectors at the rotary switch, transmission, and TCM? Disconnect the vehicle battery before you disconnect the other components to reduce the risk of shorting any pins.

I just spent some time perusing the Workshop Manual and found some information that may be helpful.

Here is a snip from the transmission diagnostics section of the Workshop Manual (pdf page 1275) that has a shortcut to tell whether the D to 4 switch or cable adjustment is the most probable cause of P0706:




You can download the Workshop Manual at this link:

Jaguar X308 Workshop Manual 1998 On

The Gear Selector Cable Adjustment procedure is on pdf page 1510

The P0706 Pinpoint Tests begin on pdf page 1469

Cheers,

Don

 

Thanks again, Don.

That gearbox overhaul was done by a company near Bordeaux here, who has been reconditioning automatic gearboxes only for the past 30 years or so.
(Around 3,000 Euro cost).

I have the manual on CD but it is crap to look something up on it.

I have nor been able yet to touch the rotary switch that is attached to the side of the gearbox. That will now be my next thing to do
as soon as my garage will want to touch it. Maybe I can start by trying to adjust the cable IN the car, but it seems to be necessary to take the seats out so the covering can be taken off.
Jag garages tell me my car is too old and ask me if I want to buy a new car.

I will keep you posted of any further developments (without the swearwords).

Thanks so much.

Takeo.

 

Dear Don,

What do you tink of this vid ?


So much for taking the console off but what do I do with the cable adjusting nuts ? Just loosen them and feel for some "center" position in the N position ?

Thanks,

Rudolf.

 

Hi Rudolph/Takeo,

Yes, I found many of the Jaguar workshop manual CDs to be frustrating to use. The nice thing about the pdf files is that many of them are searchable. In Adobe Acrobat Reader, press Ctrl+F or Cmd+F and a search window will appear if the pdf file is searchable. Enter P0706, for example, and you can move forward or backward to the next occurrence of the search term. That is how I found the "Default to 4th gear" diagnostic instruction that I snipped and posted.

That video you asked about shows the general procedure to get the console off, but I must have missed the part where he showed how to adjust the cable. See the pdf Workshop Manual page 1510 for instructions for adusting the cable.

Cheers,

Don

 

Hello Don, hello all !

This morning, around 10 am, I took he gearshift little oval cover off and dug into my tool box.

I have Stahlwille PRO grade tools, very thin and virtually unbreakable and stinking expensive too.

I could undo the rear 25 mm nut and adjusted to the back and to the front, using the R position as a middle reference, NOT the N !!!

About 3 - 4 hours of singing psalms later I could take her for a 3 Km spin.

Drove back home and adjusted the cable a tad more to the front and locked it up.

Took her for another spin, she was shifting all gears.

So, not needed to take all of the console off, only the top, undo the back nut and then loosen the front one with a screwdriver. I adjusted the cable (housing) towards the back till I had a somewhat acceptable
position and took her for another spin. She shifted normally. My nerves were tending towards a shot of moonshine by then.

So that was today.

Tomorrow I will see in how much j-gating is possible, switching into lower gears on a downhill stretch.

Also: I sortof noticed that the TCM "learns" how to adapt while driving, fuel consumption indication goes, under way, from 1 liter / 100 Km to 45 liters / 100 Km. I think that, in reality, she consumes about 15 liters / 100 Km. all kinds of roads, it is all hills and curves here.

I will keep you posted if any other developments.

Thanks,

Takeo.

 

Takeo,

That is great news! Thank you for reporting back with your success!

I have revised the title of your thread to better reflect the actual nature of the problem for future readers who may need to diagnose P0706.

Cheers,

Don

 

GRRRRRR !!!

Morning exercise !

Cold engine start. Shift to drive, Restricted performance. AGAIN.

Re-started a few times, shifts normally, I drive 1 Km, jumps out of 5th gear again.

I drive another Km and all seems OK again, does not jump out of 5th.

I stop underway, start again with warm engine (and warm gearbox) and no more problems to drive home.

So, now, I am thinking about a combination of TCM and gearbox ATF temperature ???

Intermittent problem again, but not as bad as before ???

Conclusion: I have not the foggiest idea of what is actually going on. The car is 24 years old.

We will see what happens after I drive a longer stretch on this coming Thursday.

Takeo.

 

Have any codes been triggered?

I note from your description of the adjustment process you performed, you did it with the lever in Reverse, not Neutral as the Workshop Manual specifies. Perhaps it would be worth trying it that way?

Cheers,

Don

 

I was curious why the "N" position was not used, as well.

 

Hi guys

2 resons why I did it in the R position and not N:

* I watched someone on YouTube doing it that way and he said that it worked, he added that he got P0706 because he felt something "funny" while shifing gears and said he thought that his shift leavers was not in the middle of the R position. Later he added everything was ok.

* I did not believe that and tried to adjust for a "comfortable" shift lever "feel" in N and got nowhere. I adjusted back and forth over the N position and all stayed what it was, so now I have "MY CENTER" on the R position

* In the the R pos "adjustment" I can now drive normally most of the time as long as I do not shift down. Starting takes 2 - 3 times using the key switch to get rid of the 706.

So, this is "half" an adjustment and I am nw thingking of renewing the "D" rotary switch that is found on the starboard side of the gearbox and often has dirty contacts.
BUT, the manual says to adjust the D switch: discannect the lever and from rearwards position wove 2 clicks forward to attain N. ???? Rearward is D and 2 clicks forward is R and not N ? Someone please explain ...
I will try to buy a rotary switch, replace it on the side of the gearbox and only push the electrical plug in without touching the gearbox shift positions and take it from there ....

Only dashboard notes I get is Gearbox fault and 0706.

? ? ? ?

Takeo.

 

I tend to give more credence to the Jaguar Workshop Manual than to a YouTuber....

I think the rearward position will be Park, the next position Reverse, and the second click Neutral. You can confirm this once you get under the car and can compare the shift lever position with the cable and switch position.

Cheers,

Don

 

Sorry, Don, I missed.

ok 2 clicks foward is N, I was thinking the other way round.

So, Sunday now, been driving around the village here, some 30 Km, no more fault codes whan engine and gearbox are warm. I did a "hard reset". Also, I can, now again, shift down to brake on the engine.

Must have stop-tares engine like 30 times.

I have NO idea what is going on or what I am doing, but if it says that way now, I will be very happy !

Thanks for talking to me, Don.

Takeo.

 

Hi all, hi Don !

Afternoon around 1500 Hrs.

Nice weather here, sunny, 17 + C. Almost warm.

Yesterday, my old Jag behaved correctly.

Today, I started, got all sorts of gearbox fault and other messages. Waited till engine warm and took her for a spin.

Locked in 4th gead again !

Back home, I "undid" the "adjustments" I had made a couple of days ago and, lo and behold, momore messages
and she goes like a bat out of hell. Torque converter locks up properly, engine braking through the J-gate brake works properly, everything ok !

Why ?

I have NO idea at all. (I have usually no idea of what I am doing).

NOW: wait till tomorrow, start with cold engine and gearbox and I will come back and say if I am a happy camper or not.

Have a nice day all !!!

Takeo.

 

Hi Don, Hi friends,

Me again ...

This morning I uttered the proper series of profanities driving to my doc and back in 4th gear.

Back home, I loosened the center console and, pulling it back for like 20 cm, I found that the shifter cable had fallen off the plastic slider, nut had fallen off.

Must have taken a long time and I must have shifted with that nut getting looser and looser till it finally fell off.

Put a replacement nut on the cable end and secured it with a Grower whatsit.

Took her for a spin, all worked almost properly. Maybe I may still have to play around a bit finding a proper "N" setting.

And, since I replaced a coil, she now runs on all 8 cylinders and it is a bit scary to accelerate here on the small hilly and curvy lanes.

Rudolf.