[nheidmann]

I have a 2005 trailblazer LS 4x4, This problem has been going on since november. when the gas is let off, the voltage meter drops, all lights flicker, does it a lot, only at night. took it in to dealer, they had to run tests in a dark room with a test computer, and said that GM was aware and there is nothing that can be done. does anyone else have this problem and had it fixed?? They said is was something to do with the air pump that adjusts the rich/lean of the engine. Something needs to be done here!! people get pissed over flashing lights...

 

[deathbynosleep]

mine does this also. i've taken it up and they haven't been able to fix it.

 

[MTPockets]

Yeah, that air injection reaction (AIR) blower is a high amp draw item when it kicks in. It probably catches the voltage regulator in the alternator by surprize causing the lights to go dim/bright. I bet a higher capacity battery would help this condition.

Joel

 

[tj willy]

:iagree: Both the Optima red and yellow tops are great bats. The yellow top is more suited to deep cycle pulls like winches and I would think amps. The red top offers more in the way out CCA and I would think generally more suited for everyday use. Both batteries are great about "recharging" themselves from a reserve.

Or it might help to have your altenator rewound to increase output. :undecided It is less expensive than going with an aftermarket alt such as mean green.

Just an idea.

Here is a link to Mean Green: CLICK In case anyone was curious.

 

[mjr15197]

Don't replace the battery. Don't mess with your alternator. Just let your truck idle for 20 seconds after you start it before drving away.

 

[Bulldog]

Mine does the same thing and I have sent in a detailed complaint to GM. They said there is nothing they can do. It has been happening for 50K miles.

 

[Steve02SLT]

Don't replace the battery. Don't mess with your alternator. Just let your truck idle for 20 seconds after you start it before drving away.

i don't know about nheidmann, but mine does the same exact thing. it'll happen when i'm pulling away from stop signs/red lights, so its not a matter of letting the truck idle, theres a problem with our electrical system.

 

[Dave]

Joy! Another "normal" condition for a GM vehicle. I wonder how many people would have still bought their GM car if all of these normal operating conditions happened on the test drive.

 

[mjr15197]

i don't know about nheidmann, but mine does the same exact thing. it'll happen when i'm pulling away from stop signs/red lights, so its not a matter of letting the truck idle, theres a problem with our electrical system.

You're right. The 20 second idle trick will not work for you. It will only work if your lights are flickering because the secondary air pump is running an "active" dianostic test.

Since you have a 2002, your truck dosen't have the secondary air pump. Only 2004 and newer Trailvoys with the I6 have it. Since nheidmann has a 2005 I'd still recommend he just try the 20 second thing. Even though your truck has a similar symptom, I'd suspect the cause is different.

That's not to say, however, that the electral systems in our all vehicles could not be designed a little more robustly.

 

[geneelder]

I have the exact same problem, but it only happens after I have been constant on the pedal and are coming to a stop, and only if i have the stereo up. Its normal.

 

[NJTB]

I too have the same problem. Mine only seems to happen at a stop light or a stop sign. I would say that it only happens at night, but that is the only time that I can really see the headlights and dashboard flicker.

 

[Bulldog]

You will all notice when the lights dim the battery signal drops under 12. I think there needs to be some kind of power electronic of some kind that will keep the high voltage going. Sort of like the old days when you could put a bigger alternator and coil on vehicles to feed everything equally.

 

[my-tb]

Dave Joy! Another "normal" condition for a GM vehicle. I wonder how many people would have still bought their GM car if all of these normal operating conditions happened on the test drive.


Dave I have to agree 100% Just as I think I am home free another one pops up

 

[blacklock]

My wifes 04 trailblazer is doing this light thing also. Just had it at dealership and they did some test on it and said they could not fix it.

 

[Black-Syth]

I had the same problem on my Traiblazer. Then I got fed up with it, and threw in an Optima Yellow Top. Hasn't done it since.

 

[DEZEL1]

I had the same problem here the other night on the highway. When I let off the gas the lights would flash the person in front.
This is not cool at all.

 

[tj willy]

I had the same problem on my Traiblazer. Then I got fed up with it, and threw in an Optima Yellow Top. Hasn't done it since.

(A Red Top would have served the same purpose.) Glad you got it worked out!! :yes:

 

[Valkyrierider]

:iagree: Both the Optima red and yellow tops are great bats. The yellow top is more suited to deep cycle pulls like winches and I would think amps. The red top offers more in the way out CCA and I would think generally more suited for everyday use. Both batteries are great about "recharging" themselves from a reserve.

Or it might help to have your altenator rewound to increase output. :undecided It is less expensive than going with an aftermarket alt such as mean green.

Just an idea.

Here is a link to Mean Green: CLICK In case anyone was curious.

I installed an optima red top, and I have not had this problem since, except when I got the stereo up, then there is a very minor blip if the bass hit's at the wrong time.

 

[MTPockets]

I installed an optima red top, and I have not had this problem since...

There you go.:thumbsup: U can almost bet a higher capacity battery like a red top will solve nearly every case of this. Manufacturers build NO excess capacity into the electrical systems of today's passenger vehicles. You add ANY a/m electrical accessory into the system & you will go beyond it's capabilty. I've seen this happen with many different (newer) make/model vehicles.

Joel

 

[tj willy]

I installed an optima red top, and I have not had this problem since, except when I got the stereo up, then there is a very minor blip if the bass hit's at the wrong time.

The yellow top is recommended for any deep draw (cycle) application. Winching, Car stereo Amps. I notice a sig charge drop when I winch with the red top, that is why I am moving it into the voy and putting a yellow top in the jeep. I have tons of lights on my Jeep and they have never put a strain on the red top in case you are wondering.