Where in my 2005 Chevy Trailblazer transmissiin is the 2-3 shift solenoid located? I have the oil pan off and there is not really any clear markings as which is which...

there are like 1billion cars noW doing this.

1. the gas cap was loose or bad !!!
2. theN the driver did not know it takes 30 driving cycles to clear the CEL lamp. OOPS 30? OBD2 DOES THAT. PER SERVICE MANUAL RULES, IF YOU READ THEM.
3. the fuse did not blow, or you'd have not asked where it is, I get that.!

99% of the time the cap was just loose or bad
my car the 1% time, the purge solenoid stuck
and my walmart silicon spray'd there (INSIDE IT) ended FAILURE for 50,000 more miles.
learn to buy AND USE a scan tool (borrow, rent ,buy)
tighten the cap again
scan the pCM see the cel lamp reasons./
push reset on the toll (CEL goes off if lucky and not 100 other DTC errors set)
and drive 3 times or more and the CEL stays off.

the other resets are(NO SCAN TOOL,. REALLY?)
1: PULL BATTERY LUG FOR 15MIN AND PUT BACK
OOPS RADIO GOES DEAD. dang
2: PULL ALL IOD FUSES. THE PCM MEMORY FUSE ONLY.
Ecm F29 IS IT(MEM) (PCM) 10AMPS
ALL DTCS NOW GONE, STORED. THE DATA FELL; INTO THE BIT BUCKET AS THEY SAY

IF ALL TESTS AND WILD GUESSING REPLACING ALL EVAP; VALVES. THEN COMES THE SMOKE MACHINE TESTS.
TO FIND THE LEAK
THIS IS AND EPA MANDATED MONITOR IN USA.
FOR SURE. THE 2 FUSES FOR BOTH EVAP VALVES ARE HERE.

Question edited for clarity, add maker and all the typos 'senors', 'reves', 'blazzer'.
Question moved to model category.
Please don't type in all CAPS, it is considered SHOUTING and is harder to read.

You mean 'Solenoids'?

https://www.google.com/search?q=2005+chevy+trailblazer+4.2+4x4+shift+solenoid+location

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these links will help and its the side pan How To Replace Transmission Shift Solenoid On 2005 Chevy Malibu shift solenoids on 4T60 shift solenoids on 4T60

shift timing solenoid ????? There are 1-2 shift solenoids , 2-3 an 3-4 but no shift timing solenoids . An all solenoids are inside the transmission . Do yourself a favor an take your vehicle to a qualified repair shop .

You will have to pull the transmission fluid pan off and change the automatic transmission shift solenoids change both 1-2 and 2-3 shift solenoids you also need to change out the torque converter clutch solenoid. it is spring-loaded watch the shift valve when changing the tcc solenoid and pull your dipstick out before putting the pan back on makes it easier make sure to reset codes on the computer after you are done.

He's back !!!

Inside the side cover on yours--- Jerry

No easy job- as sub frame is in the way, I
suspect

Need a trans shop

There is no such part as a shift sensor, so I assume you mean the computer controlled shift solenoids. They are inside the transmission attached to the hydraulic control valve body, to access remove ****** pan.

shift control solenoid ? Inside Pan ..Drop pan and you will see all the shift solenoids

YOUR SHIFT SOLENOID VALVES LOCATED IN THE VALVE BODY.REMOVE BOTTOM TRANSMISSION OIL PAN TO REMOVE SHIFT SOLNOIDS.

go undernieth your truck and look up at the bottem of it. if it is anything like my truck you will see your drive shaft easily (the things that runs down teh middle of your car from the engine to the back wheels) the transmition pan will be beside that closer to the engine, it looks like abit of a square (odly shaped) and either black or rusty depending on age of truck. the transmition pan will have around 17-20ish bolts holding it up, unscrew this (get an oil pan for all the oil that will come out) and your transmition filter is just under there. hope that helped