RC99TL

Got a 2nd 1739 code in 2 weeks.
Hey, why does owning an older TL mean you need to keep a code reader in the glove box?!
Anyway called my very cool parts guy at the dealer to order both 2nd and 3rd switches and he tells me both pressure switches are the same part number.

Is this true on a 99 4 speed?

Second question: do they install new switches with the (dealer warranty) rebuilds or do they swap over the sensors and relays from the old?
This is the second trans. First one replaced at 107k- I have another 65 thou on it now.

Thanks in advance...

piggylover1985

Firstly both pressure switches should be the same for 99 sp. For most 4 cyl models they have green 2nd pressure switch. The black switches are for 3rd,and 4th, but some later one also have gray switches. As long as they're same color then they're the same.

Second question i don't know how dealers do it, but at transmission shops, they normally just take them out and clean them, it it still set code for it then they might change it, most likely if you take them out and clean them they will work. If not it could be something with the wiring. They just don't go bad by themself, the clutch material from inside the transmission come apart and trapped inside the pressure switch will cause the code to come on, and worse, it would take out the transmission.

RC99TL

I usually change the 3qts every 6 thou and have already removed and cleaned the connectors.
When changing, the old fluid comes out like new and there is almost nothing on the drain plug magnet.

I am going to swap out both switches and will report if the originals were contaminated in any way.

Oh, can anyone tell me what the term "flare" means when it is used to refer to to the shift action. I have seen this in the shop manual and in the faqs.

RC99TL

I replaced both the 2nd and 3rd control switches (after getting the 3rd switch code) and all I can say is: WOW! The trans shifts so much better. It tends to hold 3rd longer than before and the shifts are crisp and firm(er). The car is so much more lively.
This is the second trans and I wonder if all the switches and solenoids are replaced with the trans or just swapped over.
Anyway it is very easy to replace these and I recommend doing it as a PM on older trans.

01tl4tl

there is a rumor the switches are supposed to be replaced with trans
BUT many seem to not be...whether lazy or profiteering is unknown

Many techs also dont transfer the vin plate on the trans- and they are supposed to