2006 Trailblazer Check Engine Lights

TJsDAZE · June 29, 2009

I have a 2006 Trailblazer 2wd 4.2 6 cyl. the chck engine light came on so I took to adv auto they gave me a code p0449 for vent valve solenoid. i found a diagram on this sight for location and had dealer replace it and new battery. Now the ABS, Stablitrak service light and Stablitrak indicator light is going on and off intermitantly at the same time, sometimes on and off sometimes stays on, this starts after veh has been on a while. when first came on was on highway felt like veh was shifting gears. hasn't done this since then. I took it to dealer said it was coding rear speed sensor but when the sensor itself was checked it was good they checked all wiring and leads connections ? Dealer said wait for lights to come on and stay on so they can get a better read. Is this good advice or are we overlooking the obvious or just misdiagnosing the problem. I am confused. Please help any help is good help.

redvett · June 29, 2009

First check for clean & tight battery connections. Who ever installed the battery may not have cleaned the terminals or properly tightened them.

TJsDAZE · June 29, 2009

I have a 2006 Trailblazer 2wd 4.2 6 cyl. the chck engine light came on so I took to adv auto they gave me a code p0449 for vent valve solenoid. i found a diagram on this sight for location and had dealer replace it and new battery. Now the ABS, Stablitrak service light and Stablitrak indicator light is going on and off intermitantly at the same time, sometimes on and off sometimes stays on, this starts after veh has been on a while. when first came on was on highway felt like veh was shifting gears. hasn't done this since then. I took it to dealer said it was coding rear speed sensor but when the sensor itself was checked it was good they checked all wiring and leads connections ? Dealer said wait for lights to come on and stay on so they can get a better read. Is this good advice or are we overlooking the obvious or just misdiagnosing the problem. I am confused. Please help any help is good help.

OK I have tightened and cleaned the batery connections. They were not very tight. No light as of yet. As I said the light is coming on and off. So I will keep you posted. Thanx for your reply.

TJsDAZE · June 30, 2009

Hey Redvette hope your having a good day The lights have not come back on since I used your advice I have driven 60 miles,the lights are usually back on by nowI appreciate your reply and so far so good. my hat is off to you, they must not have checked this at the chevy dealer. I thank you kindly. Tim

TJsDAZE · July 1, 2009

First check for clean & tight battery connections. Who ever installed the battery may not have cleaned the terminals or properly tightened them.

Hello Well I tightened and cleaned battery connections no lights for about 80 miles.The lights came back on when I returned home from work I shut the veh off and restarted no lights came back on. could it be a ground somewhere? I can't guess what it could be. Please help

bill190 · July 2, 2009

With an intermittent problem like this, it could be the sensor, the wiring to that sensor, or the electronic module for that sensor.

If the light is not staying on, all you can do is guess as to the problem if you want to eventually get it fixed.

I would start guessing at the least expensive part first. That being the sensor.

If that does not work, I would replace the wiring and connectors between that sensor and the electronic unit. Very important that connectors are replaced along with the wiring as this can be a source of trouble. (Of course no need to do that if the above replaced sensor plugs directly into the electronic control unit.)

Last I would replace the electronic unit.

Alljackedup408 · July 2, 2009

With an intermittent problem like this, it could be the sensor, the wiring to that sensor, or the electronic module for that sensor.

If the light is not staying on, all you can do is guess as to the problem if you want to eventually get it fixed.

I would start guessing at the least expensive part first. That being the sensor.

If that does not work, I would replace the wiring and connectors between that sensor and the electronic unit. Very important that connectors are replaced along with the wiring as this can be a source of trouble. (Of course no need to do that if the above replaced sensor plugs directly into the electronic control unit.)

Last I would replace the electronic unit.

+1 thats what i would do at the dealer.

TJsDAZE · July 2, 2009

Thanks for the reply. I will watch the light it did not come on today. If it keeps doing this I will start with the sensor first or have the dealer start there. Thanx for the input I will keep you all posted. TIM