I have looked at many threads on this forum to help diagnose my issue but as yet I'm at a loss, perhaps someone could offer some insight if I give my poorly kitty's symptoms? (a bowl of milk did n't help at all!)

I don't have any transmission error codes
(only a brake light error, which in this month I'll call 'a hunt for red bulb-october,')
I don't think I have an 'A' drum problem (yet?) because the transmission engages from 'P' to 'N' and 'D' within 1-2 sec
On highway I get a 'hum' that starts at 50mph gets louder (peaks at 70mph) and then disappears above 75mph but the transmission never shifts to 5th gear (all the way up to 90 mph no shift).

I've read that the car is sensitive to the electrical power so perhaps the bulb and batteries are culprits or possibly low transmission fluid maybe even tires.
Or perhaps it is something else wrong with the transmission.

I don't want to pay a lot of money for a dealer to 'investigate' the issue, I'd rather pay for the transmission re-build.
My question is whether it is 90% probability to be a problem with the transmission?

Cheers, Jon

 

After some more forum surfing, I think that the dealer I bought the car may have disconnected the battery and not followed the correct procedure to set the transmission shift points.
I'll try a hard reset and follow the procedure.

As for the hum, I don't think the two are related, possibly a wheel bearing.

 

Just for the uninitiated, how does one perform a "hard reset" on these cars. Just got my first jag and know very little.

 

Disconnect the negative battery cable and short to the positive post for a few seconds. Newer cars need to follow a procedure to have the ecu re-educate the transmission.

 

jonathan, I suspect your idea that the hum is not transmission related is correct.

 

Today I got my battery checked at Autozone and it was above the 12.5V magic number so that ruled out the battery affecting the transmission.

Kudos to popeye68 he had the same issue (transmission not up-shifting) and it is a simple fix:
https://www.jaguarforums.com/forum/x...e2/#post461698

• I did the 'hard reset' but I simply disconnected the negative terminal then positive and waited a couple of minutes, then re-connected in reverse order.
• I got the radio code from the dealer but was never prompted for it.
• I put on Pat Benatar's greatest hits and went through the re-learning/adaption procedure as per Popeye68's post.
• I'm fortunate to work in an automotive company and we have an old runway loop where we do our drive by noise testing, takes 10-15mins + an extra 10mins to log the information.
• Someone else had to go on a quiet road at 2am in the morning to have the required distance to complete the re-learning process.

The dealer quoted me over $150 for a transmission flash, thanks to this forum I've already dodged the dreaded dealers prices.


Jobs in the pipeline:

• Get windscreen chip fixed before winter really sets in
• Need to replace rear brake bulb
• Duck tape to fix tear in drivers door trim (really annoying noise on the highway)
• Check wheel bearings to find my grumpy bearing
• Replace brakes and rotor
• Use syringe and glue to fix sagging roof
• Breathe, relax and fully enjoy my new used car!