Two codes came up P0128 and P0410?

EGJR2009

MEMBER
2004 CHEVROLET TRAILBLAZER
6 CYL
2WD
AUTOMATIC
82,000 MILES

Hi. I have a 2004 trailblazer with the check engine light on. I took it to autozone for a reading and these two codes came up p0128 and p0410. I was wondering if anyone had these two codes? Because my vehicle runs and drives fine I know that p0128 has something to do with my trucks temperature which is always around 220? To me it warms up fine so I have some doubt about the codes? Maybe is a pcm problem?

Sunday, December 13th, 2009 AT 4:18 PM

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

The code:
P0128 ECT Below Thermostat Regulating Temperature

P0410 is for the secondary air injection system.
The coolant temperature code can exists due to faulty wiring or too much resistance in the wire or the sensor.
The secondary air injection code is an emission code. Your vehicle may run ok but it may not pass smog test, as the emission system is not performing as it was designed.
The secondary air injection system is designed to reduce exhaust emissions after initial engine start-up.

I have attached the step by step diagnostics for both of these codes. This will narrow down the issue and help you get it resolved.

https://www.2carpros.com/trouble_codes/obd2

Please let me know of any questions.
Thank you.

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