06 Trailblazer just up and dies

Just bought a 2006 Chevy Trailblazer 146k miles on it the end of May. Was driving it home yesterday the AC fan stops blowing in the front and the battery light comes on and the message said “battery not charging”. Then like 10 seconds of that being being on the ABS and brake light come on and it starts making a beeping sound. Then the battery,and and brake lights disappear. And then when I am pulling in to my driveway they all come back on.

So then I shut it off and try to get it started and it starts but then those lights come back on and then also the “no airbag” light pops up now too but as soon as I put it in reverse they shut off. So then I try again and this time it won’t turn over and a minute later everything electrical stops working. No lights,no AC,no windows,no seats,no dash…nothing.
I am thinking maybe the battery just needs to be charged so I hook it up and wait for a little bit etc(this next part might be wrong I can’t remember) and I start it and it turns over and starts so I rev th engine a little bit but still no electrical comes on in the inside no lights no blower no windows no seat the dash wont light up.

Whats the issue with this if anyone can help I really would appreciate it? Frankly I want to know if this is going to be a couple hundred or a couple thousand to fix.

Oh and when we bought this the front fans wouldn’t work and they would only blow air at the feet or dash. Then the stability track light came on but the dealership said they couldn’t duplicate it or no codes came up or whatever. But they fixed the AC and said it just needed to be filled and that worked with blowing cold air in the front until the door actuator would make loud clicking noises a week or 2 after we bought it. Which they said they checked when they had it and that too but it was running fine.
But a really good mechanic I have known for many years said the HVAC door actuator needed to be replaced which that would be almost $800. Anyway the big issue now is the whole electrical not working above

There are quite a few possibilities from a failing battery, relay or main fuse, a bad electrical connection at the battery or in the main power circuit, failing alternator, bad bcm etc. It needs to be diagnosed by someone that can touch it. It could be expensive but more possibilities that wouldn’t necessarily be significant.

As long as you find someone competent and reasonable. For example, a mode door actuator for your HVAC system costs around $50 for the front. This is the little motor that controls where the air comes out; floor, vent or defrost. They tend to make a clicking sound when they fail as the plastic gear gets stripped. A fairly common failure mode at that age. No way that should cost more than a couple hundred to replace. It takes 1/2 hour to do the job. So your mech could be the best guy ever but at $800 for this job he’s making a killing…

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Another place for car repairs quoted $1000 for the front mode HVAC actuator and said it would take around 5 hours. This is the part number I think but you do realize that labor is also a contributing factor to the cost

89018675-is the part # I think.

I think the first step is to diagnose and repair the charging system. Once you have the proper voltage running in the vehicle it may eliminate many other symptoms and then make it possible to diagnose many others.


These are notorious for having the ignition switch go bad and cause all kinds of issues with lights on the dashboard . This is not an expensive item to try . Google hvac reset procedure for your model and see if that will fix the mode actuator door . If it is bad and the clicking is an indication it is then yes that can be pricey because they have to partially disassemble the dash to get at it .

Right. Did you bother to look up prices on the part? $68 on Amazon. You can find same part on other sites for as low as $50 as I pointed out. The mechanic will need to charge more to cover his costs but nowhere near what was quoted to you in the price to replace it. It’s not a hard job.

I already mentioned how much labor is involved. I’ve done the job before, have you?

I tried to give you some basis based on my experience but you seem hell bent on justifying the quoted costs. By all means, carry on…

Right now it’s completely dead and won’t run unless it’s being charged but for the place we got it from to say they did a basic safety inspection and then to fight us a bit tooth and nail when we told them the issues with the Ac/other issues and then this happens really makes me wonder…

Fully charge your battery and have it tested. Parts stores will test for free if you do not have the resources. If it tests good put it in the vehicle. If it doesn’t test good, put a known good battery in it. It should start. When running check voltage at battery. It should be around 14.6 volts. If it is not, then diagnosing the charging system can begin. If it is good then diagnosis of other systems can begin.

Check the positive battery terminal for this.

And this.


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Nothing like that on thw terminal

Okay so now I guess the car starts but NO lights inside at all dash wont light up AC doesnt work radio wont work seats won’t work windows dont work

Battery is running fine but none of the interior lights dash AC fan windows seat work

He also cleaned the terminals etc and what not and then the car clicked and tried starting but wouldnt turn over but the lights in the dash came on and then he hooked it up to be jumped and then it turned over and ran the lights in the dash came on then back to the ABS no brake light came on and dinging sound and then the dash lights when off and the car woukdbt start again

Replace the positive battery cable assembly and then see what happens.


Because one cable supplies voltage to the starter, and other supplies voltage to the power distribution center.


If you have a DVM, a couple of measurements at the battery are in order. Before the first start of the day the battery should measure about 12.6 volts. Immediately after starting the engine, 13.5-15.5 volts. What do you get?

If the voltages above are ok, I’m thinking

  • one or more chassis grounds are either missing or have a corroded connection.
  • the vehicle has as some point been underwater and there’s a corroded electrical connector problem throughout.

Suggest to defer diagnosis on the other problems until the electrical power problem is resolved.

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Vehicle has never been underwater

@George_San_Jose1 has got this right. Electrical diagnosis 101. Diagnosing of any electrical problems must not start until supply voltage is in working order. That means fully charged battery with functioning charging system.

As was mentioned by another poster, I 2nd the investigation into a missing/corroded ground strap. The electrical goofballs could explain the blend door/mode select HVAC problems, electrical issue takes priority.

Yes but there has been significant clicking when the AC is turned on in the vehicle hense the actuator. This happened a few weeks before the electrical issue bit have only had the vehicle a little over a month

If anyone has disconnected the battery recently or the battery died this can break those mode doors also . A weak spot in these models . Many people have seen this happen .