Is there 2 sensors for a 2005 chevy trailblazer 4.2 ?

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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2005 Chevy Trailblazer service manual said the same 345-395 kPa (50-57 psi)

First you need to have EBCM - electronic brake control module check for DTC'S - diagnostic trouble code's . If the light is on there is a code stored . I think most part stores can do this and for free . After you find out what code is stored , looking up that code in service repair information for diagnostic trouble shooting chart would be next step . There are a few codes too.
DTC C0035 or C0040
DTC C0045 or C0050
DTC C0110
DTC C0131
DTC C0161
DTC C0186
DTC C0196
DTC C0201
DTC C0240
DTC C0241 or P0856
DTC C0244 or P1689
DTC C0245
DTC C0283
DTC C0287
DTC C0290 or C0292
DTC C0455
DTC C0550
DTC C0558

Find the code do the diagnostic's , fix the problem , wiring issue's , a sensor , bad module ,what ever it is . The light will go out then . Here is a sample of code discription .
• DTC C0035 Left Front Wheel Speed Sensor Circuit
• DTC C0040 Right Front Wheel Speed Sensor Circuit

Chevrolet TrailBlazer - Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Chevrolet_TrailBlazer
WikipediaProduction of the Blazer overlapped with the TrailBlazer until 2005, when the 2-door ...2006-2008 Chevrolet TrailBlazer LT ... The Active Fuel Management system on the V8 engine shuts off 4 of the 8 ... 2003-2005 Chevrolet TrailBlazer EXT.

Trailblazer cranks but won't start - first things to check ...

? 3:42
www.youtube.com/watch?v=4O-wplilVV0

Mar 6, 2012 - Uploaded by MAY03LT
These are the first tests that I do when I have a Trailblazer that won't start. ... Car will not start trouble shooting guide, wontcrank, wont turn over, etc. ... Chevy Trailblazer - testing fuel pressure 2002 -2004 4.2 I6 - Duration: 4:34.

It is located in the air filter tube between the air filter box and the throttle body. Look for a 4 wire connector and that is it.

camshaft position sensor located on 2003 Chevy Trailblazer with 4 2L...

check cruise control fuse and check the brake lights see if brake light working because the brake light switch will deactivate cruise control when brakes is applied.if brake lights dont work either fuse blowed or switch bad.if all is good have vechicle code scan because cruise control control by PCM and vechicle speed sensor and thottle actuator control motor.

Hi.

The Chevy Trailblazer 5.3 and 4.2 engines have two knock sensors located at the lower sides of the engine block.

Below two diagrams showing locations first is from 5.3 right second 4.2 left.

could be the oil pump in the motor.