Jaguar Forums - Jaguar Enthusiasts Forum - XJ ( X351 )

Transmission Swap Mystery � P0740 + P2764, Converter or Something Else?

JacobG1996 — Sat, 23 May 2026 01:36:13 GMT

Hello everyone,

This one is kind of a mystery, and at this point, I�m honestly a little confused and would love to hear some opinions. I tried to explain everything clearly below because I feel like I may be overlooking something. Originally, I replaced the transmission and torque converter because my car had been throwing a P0740 code for a few months. Then one day, while making a left turn, the car suddenly stalled and came to a hard stop in the middle of an intersection. It made a loud clicking/ratcheting sound that almost sounded like Park trying to engage while moving. After that, the car would not move. I talked to a lot of people and read a lot of posts, and almost everyone said that P0740 usually points to a bad torque converter. Since I was already planning to replace the converter, I decided to install a lower-mileage transmission at the same time instead of replacing only the converter. I installed a complete transmission, torque converter, and donor mechatronic from another XJ with around 48k miles. What has me confused is that I�m still getting P0740, and now I�m also getting P2764. I know anything is possible, but it would seem pretty unlucky if both torque converters happened to be bad, so I�m starting to wonder if something else is actually causing this, maybe even electrical, or if the new transmission TCM is a replacement, do I need to configure it in SDD?

Vehicle:

2012 Jaguar XJ (X351)
5.0 Naturally Aspirated
ZF 6HP28

Original issue:

The original transmission had a persistent P0740. The car actually drove mostly normally for a while. Then one day, while turning left, there was a loud clicking/ratcheting sound that sounded almost like Park trying to engage while moving. The car stopped abruptly and would no longer move afterward, which is similar to what the car is doing right now.

Replacement setup:

Installed transmission and torque converter from a 2013 XJ (~48k miles)
Opened transmission only to replace:
- Filter
- bridge seal
- cylindrical/mechatronic seals
- connector sleeve seal
Used correct ZF seals
Followed the ZF torque sequence carefully
Did not disassemble valve body
Did not remove individual solenoids

Current symptoms:

The car starts and drives, but shows that it has a gearbox fault.
Transmission engages gears somewhat normally, but p0740 and p2764 don't disappear. P0740 does for a minute if I clear the codes, but comes back pretty quickly.
No major shudder
No major slipping
No major harsh shifts
Shifts may feel slightly elevated, but nothing dramatic.

Important behavior:

P0740 seems to remain stored consistently
P2764 only appears after revving the engine to around ~4000 RPM
Sometimes reverse works, but sometimes when I put it into reverse while I'm backing up, it will suddenly stop, and I can't hear the parking pawl clicking into position.

Verified:

Transmission fluid level checked multiple times and appears correct using Pentosin ATF6
The charging system confirmed good
Transmission module voltage while running is normal

Current transmission DTCs:

P2764 � Torque converter clutch pressure control solenoid control � circuit low
P0740 � Torque converter clutch solenoid � circuit/open

Other modules:

Intermittent U0402 / invalid data received from transmission control module after transmission faults.

My question:

Most Jaguar techs I�ve talked to say P0740 almost always ends up being the torque converter.

But:

I now also have P2764--Torque converter clutch pressure control solenoid control - circuit low
P2764 appears conditionally (mostly high RPM)

Does this sound more like:

Am I the one in a million that actually has a dead TCC solenoid, which is causing P0740?
Donor mechatronic issue?
Since it's showing up in both transmissions, is it possibly a software or even an electrical harness issue?

Trying to decide whether to:

Replace solenoids?
Replace mechatronic?
Pull the transmission again for the converter?
Investigate wiring/configuration first?

Would love to hear from anyone with actual X351 / ZF 6HP28 experience! Besides this major problem, the car is running great and I would genuinely appreciate any advice or someone who has experienced this before. Thanks for everything, and I look forward to hearing any feedback!

Attached Files

ABS.pdf (99.6 KB)

GSM.pdf (100.3 KB)

SUMB.pdf (99.6 KB)

TCM INFO.pdf (108.8 KB)

Trans Codes.pdf (100.4 KB)

Trans Live Park.pdf (265.5 KB)

Valet mode Don�t know pin

roadbird — Wed, 20 May 2026 23:38:15 GMT

I bought car from auction it�s in valet mode. No trunk open anybody know reset pin. Dealer out of business

Throttle Body Heater Hose... Where does it go? '11 NA

JHendo — Wed, 20 May 2026 04:45:54 GMT

So i was losing coolant in the '11 onto my belt somewhere and it was being dispersed rather effectively, all over the oil filter housing and anywhere the belt could sling it. Had to spray it all clean to begin my search, only for it to be that somehow the heater hose for the throttle body has gotten into the pulley for the water pump, and worn a small hole in it. Despite my best efforts I cannot find a diageam that shows just where this hose leads to at its other end as it disappears under the upper intake into the valley with no other end visible. Can someone fill me in on where I need to get to in order to replace it? I am hoping against hope that I don't need to remove the intake for a basic hose replacement, but nothing will actually surprise me. If you know, please share, if you have a diagram or image I have been inable to find that would be even better. Thank you in advance for your assistance.

B0004-11 drivers knee airbag but no airbag or working present.

starSLA — Mon, 18 May 2026 13:31:31 GMT

XJ 2012 3.0 v6

Fault code showing intermittent fault suggesting it is the ground cable for drivers knee bolster airbag but after spending two days I have come to understand that there has never been an airbag or wiring to support an airbag.

Has anyone experienced this before? If so what was your solution.

Thanks

Need Advice On Removing Stuck Injector

Durvelle27 — Sun, 17 May 2026 13:42:41 GMT

What's up guys been awhile but I'm back again and need some assistance. I have a 2015 XJL Portfolio and my Injectors are leaking so I am ordering a whole new set. Issue I'm having is on the driver side the 2nd cylinder I can do get the injector out. It has been soaking for over a weak with carb cleaner and I have the sliding hammer removal tool but it will not budge and it's the only one left. Any advice would be greatly appreciated as I don't want to break it.

Rear lower control arm replacement qustion

mux101 — Fri, 15 May 2026 09:05:19 GMT

Hello everyone,
I�m planning to replace my rear lower control arm on my 2012 XJ because the bushings are making all kinds of noises. My car has rear air suspension and to remove the rear control arm I have to disconnect the air shock. I�m planning to disconnect the battery and air out the shock from the top to make the installation easier. After assembling and connecting the shock the car shoul inflate the suspenion back to standard ride height right? Or do you have any advise before I start?
I don�t have any diagnosis for this car to air out the suspension before I start.
Thank you very much for your help.

Mina Gallery Intake question

Supercharged Jag — Thu, 14 May 2026 20:18:47 GMT

Hi all, my intake is cracked near the throttle body area on my 12 XJL SC 5.0, and I will need to buy a new one. I just ordered the Mina gallery one, but I am now seeing a lot of mixed opinions (mostly negative) saying due to theirs being metal, it increases the IAT temps drastically, especially when idling. Also apparently the Mina one causes worse performance?

Should I go through with Mina order or cancel and buy an original/plastic one?

I was mainly looking to get Mina because I thought metal would mean better longevity/durability over plastic.

Ads continue to become even more ridiculously annoying

rothwell — Wed, 13 May 2026 14:55:43 GMT

Posted this here so it's clear why I am pulling back. Posting complaints in the "correct" section just gets ignored anyway.

When the greed of IB gets to the point where I can no longer see more than a single line of posted content, I think its time I re-evaluate my desire to contribute here. The new ad row at the bottom is just too much.

The full screen popups were bad enough but at least they were not constant like this new BS at the bottom seems to be. It's all very disappointing, but not surprising of the "social media world" whose entire game is about bleeding people slowly with ever increasing ads and less actual value. Give me space to enjoy contributing and I will. But I am not coming here to fill IB's pockets while I get nothing but frustration.

Sad thing is, I doubt that IB even cares. That is what it feels like at this point to me. I just can't continue to feed this beast that seems to be more comfortable working against our best interests than providing a valuable service. Hoping things change for the better and I see a reason to get more involved again. I am all out of reasons at this point.

Intercooler/Supercharger pump location

Supercharged Jag — Tue, 12 May 2026 23:24:54 GMT

Hi all, the IC pump on my 2012 XJL SC seems to be intermittently working or may even have stopped working all together. My SC temps are very high (north of 180 Fahrenheit).

I swapped the pump today with the Bosch 010 and was wondering did I replace the correct pump? I saw a few forums where some folks accidentally replaced the heater pump rather since they are identical? I looked everywhere and couldn�t see another pump. This one was accessed/replaced by removing the front bumper.

I traced the hose that connects to the pump, to the supercharger intercooler, so I�m assuming it�s correct, but would like confirmation if possible.

Also, is it possible to bleed the coolant system by just parking on steep hill and leaving cap off + running high heat?

Jaguar Xj x351 2016 3.0 Diesel Metal Shavings In Oil Filter

Lukas_03 — Tue, 12 May 2026 10:46:46 GMT

Hello everyone,

I have made made an unfortunate decision to purchase two jaguar xj's x351 3.0 diesels for me and my wife, both 2016 model which both seem to have developed engine failures. If I am correct both cars have the sdv6 gen 2 engine with mileages of 80k and 110k.

The first car has no weird noises coming from the engine apart from a chain like clutter when cold starting the engine but apart from that sounding sweet. The oil filter has been cut open to reveal oil shavings in the filter.

The second car has the same cold start chain rattle noise and a very slight knock upon accelerating but nothing on idle yet, but much more metal shavings in the filter than the other one.

Before I start digging deeper and looking at options I just wanted to see if anyone has any opinions on this and what the possibilities could be.
From my limited knowledge and what I have read I am guessing its the main bearings that have failed? I was told by a mechanic previously that the chain rattle sounding noise is usual from this engine when on cold start, is it something in relation to that noise?

Would love to hear your expertise and opinion on this, thank you!

Jaguar XJ 2010�2019 Upgrade � 13" Android Screen with CarPlay & Modern Infotainment

carputech — Mon, 11 May 2026 06:39:31 GMT

Hi XJ owners,

We�re CarpuTech, a professional manufacturer specializing in infotainment upgrade solutions for luxury vehicles. If you�re driving a Jaguar XJ / XJL / XJR (X351, 2010�2019) and want to modernize your interior technology while keeping the classic luxury feel, this upgrade is designed for exactly that.

We�ve developed a 13" Android touchscreen system specifically for the XJ platform, bringing modern connectivity and a much improved user experience without changing the original elegance of the cabin.

👉 Product link:
https://www.carputech.com/products/1...-car-radio-gps

Key Features:

📱 Apple CarPlay & Android Auto � seamless access to navigation, music, calls, and apps
🧠 Android system built-in � install apps like Google Maps, YouTube, Spotify, Waze, etc.
🖥️ 13" HD touchscreen upgrade � larger, clearer, and more responsive than factory display
🔄 Retains OEM Jaguar system � switch between original interface and Android anytime
🎵 Supports factory audio system � keeps original sound quality and amplifier integration
🎮 Maintains factory controls � steering wheel buttons and original functions still work
🎯 Plug & Play installation � no cutting wires or complex coding required
🧭 Built-in GPS navigation � modern navigation experience with real-time traffic apps

This upgrade is ideal for XJ owners who want to bring modern infotainment features into a full-size luxury sedan without compromising Jaguar�s original design language.

The X351 is still one of the most elegant luxury sedans on the road�this upgrade simply brings the tech up to today�s expectations.

If you have any questions about compatibility, installation, or real-world performance, feel free to ask 👍

� CarpuTech Team

Technical Inquiry for 2015 XJ X351 3.0D

Harold Lee — Fri, 08 May 2026 07:40:48 GMT

Hello. I am the owner of a Jaguar XJ 3.0d (2015 model,). I am writing to request an official technical assessment to determine whether there was any negligence in the work carried out, following a system failure that occurred immediately after the battery was replaced by an external contractor.

1. Details of the Incident

Date and Location: 6 May 2026, at an external battery supplier.

Work carried out: Replacement of the main and auxiliary batteries (installation of Solite AGM batteries) and battery registration (BMS reset)

Driving conditions: Immediately after the replacement, the vehicle was driven normally for approximately 230 km on the highway. (no warning lights or electrical faults during the journey)

Problem occurrence: Immediately after arriving and stopping, the rear-view camera failed to operate, the door locks jammed, the smart key was not recognised (the message �Check key and smart key not found� appeared) and the power was cut off

2. Current vehicle status (diagnostic results from specialist workshop) When connected to the JLR-specific diagnostic tool (SDD), the vehicle VIN is recognised, but communication with the BCM (Body Control Module / CJB) is impossible; damage to the BCM module is suspected.

Upon disconnecting and reconnecting the main connector of the rear seat fuse box, the vehicle temporarily entered the ACC ON state, but the power to the entire interior was subsequently cut off again. No signs of water ingress or corrosion were found on the BCM connector located under the passenger�s feet.

3. Official Enquiry: We request the technical opinion

Question 1: When replacing the battery in this model, is there a possibility that a lack of connection to the �backup power� or voltage sparks (surge voltage) during the terminal connection process could cause damage to the internal communication chip or hardware of the BCM?

Question 2: Can the fact that the vehicle was driven normally for over three hours on the route (with lights, air conditioning, etc. in use) serve as evidence of the alternator�s normal operation?

Question 3: If an AGM battery from a specific brand (such as Solite) is used instead of a genuine specification battery (such as Varta or Delco), is there a possibility that differences in internal resistance or voltage instability could cause cumulative damage to sensitive modules such as the BCM?

Question 4: If a vehicle that was functioning normally prior to the battery replacement exhibited this communication failure immediately after the first long-distance journey following the replacement, I would appreciate your expert opinion on whether this should be regarded as a typical failure due to the vehicle�s ageing, or as damage caused by an electrical shock during the replacement process.

Thanks
Harold

Sunshade

Jumpykitty — Thu, 07 May 2026 13:21:27 GMT

Hey, can someone tell me which part I�m missing here that�s supposed to hold this in place? Everything still works, but because this part is missing, the sunshade has stopped moving in any direction.

SDD on a 2019?

lotusespritse — Tue, 05 May 2026 19:09:48 GMT

For all other Jags, they seemed to have switched to Pathfinder around 2017, but I recently read that Jaguar kept the X351 on SDD throughout its life, probably because they didn't think it was worth investing in the platform at the end of its life.

Has anyone actually used SDD on a 2019 XJ to confirm? Is Pathfinder needed for any specific operations on a 2019?

2010 to 2019 XJL Illuminted doors sills available.

knowit — Sat, 02 May 2026 15:48:10 GMT

I am about to list three illuminated door sills for an XJL for sale on ebay. Thought I would post here first. The only one I do not have is the left side front. Work perfectly. Pics coming. Not sure what they are worth.