Hello again. I am happy to be part of this Jag forum. My 1994 XJ6 is giving me troubles, Transmission light is coming on while I'm driving and when I slow down. My car has 73,000 miles on it. Any tips on what I'm looking at?


Thanks,


Rosco59

 

I've moved your question from New Member Area - Intro a MUST to XJ40 forum. Members here with the same model will be able to help.

Please follow the advice I gave in my reply in post #3 to your original Intro:

https://www.jaguarforums.com/forum/n...-owner-139142/

Graham

 

Hi rosco59,

Welcome to the Jaguar Forums!

I assume you've checked the level and condition of your transmission fluid. For a proper check, drive the car at 45 mph or more for 15 to 20 minutes or more, then park on a level surface. With the engine running, depress the brake pedal and move the gearshift lever through all the gears, holding it in each gear until you feel that gear fully engage. Then return the lever to Park. Remove the transmission dipstick and wipe it clean. Reinsert it and carefully withdraw it. The fluid level should be right at the HOT line, and the color should be bright red and translucent. Even just a little low (or overfull) can cause problems. If all is well:

The most common cause of the transmission warning lamp (and Limp Home Mode or LHM) has been oil contamination of the electrical connector for the Throttle Position Sensor (TPS). The TPS is mounted on the underside of the Throttle Body (TB), and on our '93 its electrical connector is mounted on a bracket on one of the intake manifold elbows just to the left of the TB. Spray out the connector with zero-residue electrical contact cleaner, allow to dry and reconnect.

If that doesn't resolve the issue, you may have oil contamination of the TPS itself. Because of where it is positioned, oil that is drawn into the intake through the crankcase breather system tends to drip down the butterfly valve shaft into the TPS, where it collects and eventually causes problems. Many owners have drilled drain holes in the TPS case so it can be flushed with contact cleaner. The holes are then left open so future oil contamination can drain out. Below is a link to photos showing how I did it:

Welcome to Jag-lovers - Members Photo Viewing Page


Another possibility is oil contamination or looseness of the main electrical connector on the left side of the transmission:

Welcome to Jag-lovers - Members Photo Viewing Page


If cleaning the TPS doesn't resolve the issue, follow John Ping's excellent diagnostic procedure and you'll track down the cause (you will need to register and log on to the Jag-Lovers forum, but it's free and there is lots of great XJ40 info there):

Jag-lovers' Ebooks


The only time our transmission warning lamp was not due to an issue with the TPS, I used John's procedure to trace the problem to the Transmission Control Module (TCM), where I found a cold solder joint:

Welcome to Jag-lovers - Members Photo Viewing Page


And a couple of other transmission-related services I've performed to rule them out as causes of LHM:

Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page


Please keep us informed!

Cheers,

Don
__________________
Don B

'04 X350 XJR Sport 4.2L SC AJ33 V8 98K mi.
'93 XJ40 VDP 4.0L AJ6 197K mi.
Ex-'88 XJ40 Sovereign 3.6L AJ6
'04 BMW E46 325i

Jaguar Acronyms, Abbreviations & Terms: http://tinyurl.com/JaguarAcronymsTerms

Jaguar Original Equipment Manufacturers (OEM): http://tinyurl.com/JaguarOEMs

Jaguar Terminology Database: search the above lists courtesy of KrissMotors

My X350 and XJ40 Phototutorials: Welcome to Jag-lovers - The Members' Photo Album

 

Don't forget about the 'crappy' blue Hella relays.

Here is some info that is available in the large file download area. (that nobody reads)

bob gauff

 

Bob - you'd be surprised.

…and ever grateful for you and others who took so much time to put them there and continue to share your knowledge with the rest of us!

Cheers,
Scott