ZF gearbox faults, root causes & Troubleshooting
 

With ref to Jim's request for stickies I think

that this should be included:

Everything about your ZF 6HP26, 6HP19, 6HP28 transmission issues | BMW LOGIC7

Agreed and should be a sticky in the X150 forum as well. Thanks for posting.

Interestingly, there is a link for testing out the MOST BUS network too which would also benefit X150 owners.

This should also be added if it isn't already.

Thought I could add a comment here on what I suffered

04 xj8 n/a

(She) cat threw the abs light

10 miles later , cat went into transmission gear faults and basically wouldn't shift out of second gear . Felt incredibly a bit like the trans was toast clanks and squeals and all kinda sh!t. So I replaced the driver rear abs sensor with a rock auto part and boom , all was perfect again


transmission didn't like what the abs sensor wasn't saying and acted up for it

spread the wealth guy's .
this should definitely be in the s type stickies as well !!!

thanks

Last week a similar series of events happened to my 2008 XJR. Trip #1 ABS fault & 20 miles home. Trip #2 ck engine light on start, after 2nd shopping stop 2nd, neutral, repeat, repeat, gearbox fault and 10 miles home in 2nd. Car has been at dealer for 3 1/2 days. Haven't heard anything.

I've made it a sticky now and copied to the S Type, X250, X150 and X100 sections.

Legend > Norri

I will add ZF recommendations then as well

Mercon CAN be used in your transmission
 

I'll also add these two spec sheets that enables us to discern that Mercon is an acceptable alternative to ZF ATF M-1375.4

Mercon sp

So much cheaper and my very complicated diesel ford 5r-100takes the same . The 5r-100 is widely known as a transmission that can only take mercon SP. there is no knockoff (that I know of) for mercon sp

Just an opinion , others may wish to use fluid of ther choice

2004 XJR Transmission Problems
 

2 weeks ago less than 1 mile from warmup the I got a rough idle, a "transmission fault" and Restricted Performance. The transmission jumps from drive to neutral and bangs back into drive when trying to accelerate. I had the car towed to the shop that replaced the transmission a year ago. They replaced the transmission, mapped it and its still doing the exact same thing.

here are the codes it has now:

p1672
p1696
p302
p1316
p1582

The only mod to the car was the replacement of the air socks to Arnott's (over a year ago). My mechanics are scratching their head's.

Any idea's?

The first two codes relate to a CAN error which is possible bad connection in a CAN

connector or wiring fault in the CAN network.

If you ask me your guys are going to be scratching their heads for a lot longer.

Hi pmwestx,

Since you have posted only P-prefix (Powertrain) codes, I suspect that your mechanics do not have a diagnostic system capable of reading the proprietary Jaguar C-prefix (Chassis), B (Body) or U (Undefined, mostly Network-related) codes. Given the P codes you have, I would be surprised if you don't also have some U codes as well. Knowing those codes would provide a more complete picture and help narrow down the diagnosis.

At the link below you can download the full Diagnostic Trouble Code Summaries guide, which explains each code and gives Jaguar-specific possible causes:

Jaguar X350 DTC Summaries Guide

Given your symptoms, I a surprised you do not have at least one code for a problem with the Transmission Control Module (TCM). Are you certain the list of codes is complete?

The rough idle could be caused by the misfires in cylinder 2 (P302) which were severe enough to cause excessive emissions (P1316).

As merion1 mentioned, the first two codes indicate problems with the CAN (Controller Area Network, the primary digital communication network for the powertrain and other critical systems). Your codes both relate to communications between the Engine Control Module (ECM) and Air Suspension Control Module (ASCM or ASM) (P1672, P1696). However, problems anywhere in the CAN may cause problems throughout the network. This is what prompts me to suggest having the car scanned by a diagnostic system capable of reading all of the proprietary Jaguar codes, assuming your mechanics' system lacks that capacity.

Cheers,

Don

Dealer repair invoice: "left rear speed sensor has made contact with reluctor ring on axle shaft. Grind / clean ring replace sensor first , in attempt to avoid axle replacement"

And all is well after some local driving. Slipping and sliding in the winter then an ABS fault that clears itself after awhile has been a recurrent problem with this car. Dealer previously replaced one sensor under warranty.

Here is a couple of pics where analysis were performed between LG6 and Mercon SP. Please note the top of each pic. Jaguar specified Shell M-1375.4. Ford had a lot of internal conflict early from a service standpoint when they chose ZF's tranny for their use, specifically for maintenance for the ZF, and the cost of LG6.

Resolved
 

The fault was not rooted in the transmission or the TCU. Cylinder #3 had a cracked spark plug. Believe it or not, it was creating an EMI strong enough to effect and confuse the ECU. Replaced the spark plug.....all problems immediately resolved. Unbelievable....had I payed attention to the original set of facts (misfire and transmission fault occurring at the same moment) I would have realized that the transmission can’t cause a misfire, while a misfire is more likely to have an effect on the transmission.

Resolved
 

The fault was not rooted in the transmission or the TCU. Cylinder #3 had a cracked spark plug. Believe it or not, it was creating an EMI strong enough to effect and confuse the ECU. Replaced the spark plug.....all problems immediately resolved. Unbelievable....had I payed attention to the original set of facts (misfire and transmission fault occurring at the same moment) I would have realized that the transmission can’t cause a misfire, while a misfire is more likely to have an effect on the transmission.

Wow! How was that discovered?

Hi, I have aborted the tcu while erasing adaption values. Does anybody know, if it is possible to reprogram it with the original Jaguar Software?
It only shows up with no calibration for this model.
On Thursday I have an appointment with the local dealer for reflashing.
I have remanufactured the valve body.
You can take a look about the pictures in this link:
ZF6HP26 Überholung

Remanufacturing (tightening with gaskets) is only one thing. After replacing the full valve body including tcm, the transmission shifts fine again.
My problems have been the following:
Clunky down shift 3-2-1, failed upshift 2-3, TCC rpm cycling, harsh D and R engagement
I have tried to use a new separator plate and used the zip kit. Shifting 2-3 got solved.

So the real root couse are the valves themselve and or the solenoids.

If you have similar issues, remove the valvebody and check, if some parts in your transmission are brown coloured and if the oil smells strange. If not, the mechanical part is fine in the transmission, only valvebody should be renewed. My one had 110000 miles.
Rpm cycling needs a new torque converter.