Greetings to all!
I had my alternator replaced 1 1/2 yrs ago because it was not charging the battery, and because of this (I think) I started having Electronic Parking Brake & Transmission Faults showing on the dashboard display (blinking light and beeping once moving fast the 5 MPH) saying Unable to apply Parking Brake. Once the battery and alternator were replaced, the problems disappeared until last week, when I got the EPB fault again AND the "Transmission fault" warnings. I had incidentally noticed a few days before this happened that when the engine was off but the ignition was on, the windows and wipers ran much more slowly than before.
I was less concerned with the EPB than the Transmission notifications, as when the car was cold and I would drive 200 meters or so, the transmission would go in to "Limp Home" mode (3rd gear I believe?) and I would have to stop, turn off the car and wait 2 minutes or so before restarting. This would happen 2 or 3 more times before I would restart again and the problem was gone until the next time I started the car when it was cold. The shifts all feel smooth and normal once the car has been running once the engine is warm.

So I took it back to where I got the Alternator, the mechanic checked the battery and said it was not being recharged by the Alternator, and that I was running on the battery alone, now almost dead. He called the people who had sold it to him, and they asked that he send it back to them for them to check it. He did so, and they told him the alternator had "shorted" and sent him a new replacement alternator, which the mechanic said was now working fine and is charging the battery at around 14 volts. I went to get the car, and 200 meters or so after leaving, the Transmission code came back on! I had hoped that it was tied in to the same lack of battery power as the EPB warning (which was reset and now works fine), but no such luck! It still comes on a few times until the engine is warm.

The strange thing is that if I stop and restart the car 3 or 4 times before the engine is warm, it then runs fine (very smooth and normal up and down-shifts and kick-downs) with no more "Transmission Fault" warnings. But the next morning after a cold night it does the same thing again.

I disconnected the battery negative terminal for a few minutes, hoping it might clear and reset as with the EPB, but that didn't appear to work.

PS: I had the transmission pan replaced by Jaguar (a nightmare in itself!) about 2 yrs ago as well, as it was leaking through a small crack (it's made of plastic I found out), and they checked it and changed the fluid at the same time. I have seen no leaks at all of any kind under the car since then.

I'm wondering if anyone has had a similar experience, or might be able to share some insights? My car has 110,000 miles on it.
Thanks for any advice offered!
Stan

 

Once the replacement alternator was installed was the battery charged to at least 12.6 volts? If you have a multimeter, check the battery and let us know the voltage reading.

Inquiring minds want to know...

 

Yes the mechanic said it was fully charged and I believe he mentioned that the alternator was charging at around 14 volts if that makes sense?

 

A friend of mine back in the US (who was the head mechanics and teacher at Daimler-Chrysler teaching mechanics from dealerships around the US how to work on cars before they hit the market) mentioned that I might want to ask a mechanic to perform a VD test (I asked if he meant a Venereal Disease test LOL!) on the car by running a wire between the alternator + and - side to the battery with everything on (blower, lights, wipers, stereo etc) to see if there might be a Voltage Drop.

 

I've had some fault codes including transmission thrown at me last year, reading up on here lead met to battery being potential cause (although it was replaced early last year).
When I measured, the voltage over night dropped to about 12V which is too low according to what I read on this forum.
Had the garage check the condition of the battery (under load I think) and they found battery was ok however not fully charged; their advice was to charge the battery with a charger overnight.
Apparently this charges in a different way the the altenator does; I have found the voltage of the battery is now just under 13V

Not sure if this has anything to do with your issue, but if battery has been drained as you write, it might be good to check what condition it is in.

Good luck!
Han

 

Hi Han! Thanks for the heads up! I'll have it checked now that I've driven a bit since picking it up!

 

If you own an S-type, three critical items to own are a good battery charger, a digital multimeter and a code reader that can handle Jaguar proprietary diagnostic trouble codes. Those tools, combined with the expertise of this forum can save you a great deal of money in the long run...

 

I guess I would need to find one of those tools that reads the proprietary Jaguar codes! Probably costs and arm and a leg? Do you know of any I can look up?

An interesting aside: All of these transmission faults, when displayed, are after I start the car cold, put it in "Drive" and roll away. The last time I started it, I decided to keep it in "Park" and let it warm up, thinking that perhaps that would help.
After about 2 minutes of idling in "Park", the transmission fault lit up again, the 1st time I'd seen it do so while not actually driving. I let it keep running for another 5 minutes or so, shut the car down, gave it 1 or 2 minutes and when I restarted and drove away nothing showed up, all was normal with smooth shifts all the way to the Autobahn where I drove for 30 KM at between 180 and 220 kmh, the transmission smooth as silk.
Four hours later (the temperature was then 4 degrees Celsius), I started up again and drove off gently, and no warning came up!
Which brings me to a question. I have seen in a few other threads that somehow there is something referred to as start cycles, and that codes clear after 5 starts when there are no issues to report? Sounds a bit strange but I wonder if that's what has happened once my alternator was replaced?

 

BassplayerNYC: Any of the earlier iCarsoft line, e.g. an i930. will do the job.

iCarsoft I930 Land Rover Jaguar Diagnostic Scan Fault Code Reader Tool | eBay

(I have no connection with this vendor)