Weak Battery Cause Of Rough Transmission Shifts?

[RX in NC]

2004 RX330 AWD, 114,000 miles. Wife has recently begun complaining about harsher shifts than usual. Some days are normal, some days are not. Due to transmission failure under warranty by her previous 2000 RX300 AWD, I do a drain-and-fill every 30,000 miles using Toyota Type T-IV ATF just to be sure the fluid stays fresh. It looks great and sits right at the proper level for both hot and cold checks using the dipstick....

Our 2005 Jaguar S-Type sedan has a known issue that when the factory battery begins to die, it plays havoc with the many onboard computers and begins to cause operational issues. The issue most commonly reported by other S-Type owners is that the normally smooth-as-butter ZF transmission begins to lurch and jolt on occasion. Sometimes, even transmission fault codes are thrown. In 95% of these cases reported on the Jaguar forum I frequent most, a new battery fixes the issue completely....

Anyone heard of a similar issue and fix for the first-generation RX330 or ES330? As complex and interconnected as the electronic modules in all vehicles are these days, I'm hoping that a new battery could very well be my fix. The vehicle still has its factory battery (now pushing 8 years old) in which I've kept all six cells properly filled with water over the years. Never had a starting issue, just this intermittent transmission complaint from my wife....

[jaswood]

2004 RX330 AWD, 114,000 miles. Wife has recently begun complaining about harsher shifts than usual. Some days are normal, some days are not. Due to transmission failure under warranty by her previous 2000 RX300 AWD, I do a drain-and-fill every 30,000 miles using Toyota Type T-IV ATF just to be sure the fluid stays fresh. It looks great and sits right at the proper level for both hot and cold checks using the dipstick....

Our 2005 Jaguar S-Type sedan has a known issue that when the factory battery begins to die, it plays havoc with the many onboard computers and begins to cause operational issues. The issue most commonly reported by other S-Type owners is that the normally smooth-as-butter ZF transmission begins to lurch and jolt on occasion. Sometimes, even transmission fault codes are thrown. In 95% of these cases reported on the Jaguar forum I frequent most, a new battery fixes the issue completely....

Anyone heard of a similar issue and fix for the first-generation RX330 or ES330? As complex and interconnected as the electronic modules in all vehicles are these days, I'm hoping that a new battery could very well be my fix. The vehicle still has its factory battery (now pushing 8 years old) in which I've kept all six cells properly filled with water over the years. Never had a starting issue, just this intermittent transmission complaint from my wife....

The very first thing I would do is remove, clean, and burnish the battery posts and connections. The engine/transaxle controlling ECU would then have to relearn the optimal engine/transaxle control parameters and now with a more SOLID 12 volt voltage source. If the problem continues then a new battery might be warrantied.

The RX330 series makes use of DBW to lighten the stress on the transaxle during during power shifts so I wouldn't bother with doing the ATF changes unless the ATF odor or color is suspect. Also, the RX330 does not use a VC (lower driveline stress) so it does not "drive" the rear except under TC activation.

[RX in NC]

Thanks for the suggestion to clean and burnish the battery terminals. I'll do this as an initial (and cost-free) step, but at nearly eight years old I'm thinking the battery may be heading off into the sunset. If it is, I surely hope that a new battery rectifies my wife's transmission complaints....

[RX in NC]

Update:

The factory battery began to die a quick death yesterday afternoon, barely capable of starting the vehicle this morning. Just finished replacing it with a new one from Johnson Controls. We'll see if that resolves the intermittent transmission shift quality issues....

[tiguy99]

Did it fix the problem? My wife's RX300 is starting to have the exact same issue.

Dying battery for a few days now.

Today on the way home the car had a wierd shift between 1-2 and 2-3.

Almost like its struggling to shift.

Started
worrying internally for a second until I noticed the replace rear
taillight bulb icon flickering like it was a strobe light while we were driving vs staying constantly on like it did before.

The rest of the dash was ok and didn't flicker.

Am going to replace the battery with a new one this week.

Just want to confirm if you had the same issue and fixed it with a fresh battery

[sadclown]

Yes. weak batteries and voltage fluctuations can definitely cause transmission problems.