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#99 of 292 Re: Battery goes to 7.0 volts [ajscott19]
Nov 03, 2009 (8:05 am)
Hey guys... just thought I'd throw my 2-cents in here. Last week I started experiencing a similar issue with my 2005 Trailblazer LT. I work evenings (unfortunately, in a bad part of town) - and upon leaving my shift at 10:30 pm I noticed my headlights (and dash lights) would flicker. They never completely went off, but would pulse or flicker. Initially I thought perhaps I'd hit a rough patch of pavement, and the flicker I saw on the road in front of me was a result of uneven pavement.
The further I drove on my route home, the more I noticed the flicker - and quickly discerned that there was an issue with my vehicle. As the lights would flicker, my battery guage would pulse or fluctuate. It varied between roughly 11-14... but only fluctuated when the lights would flicker. Immediately I called my dad, who like I - thought it was probably the alternator going out. (Typical symptoms of a faulty alternator.) Luckily I made the trip home safely... but obviously worried because had it broken down in my employer's area of town - YIKES!
So, the next day - I take my truck into a local shop. They replace the alternator - $480 later (gulp), I'm back on the road. Don't notice anything odd for 4 days. Then LAST NIGHT, the pulsing is back. Single girl, no family for 3 states - and having been unemployed for the last year, immediately I peg the worry meter because even I (with my limited knowledge) recognize that it's probably more than an alternator issue at this point... and honestly, I'm stone cold broke.
So again I make it to work with the incredible blinking car - and again call my dad. During my shift, he did a bit of research and found the following...
(I have not confirmed this with a mechanic, nor discussed it with the GM Dealership - but I followed the 30-second idle warm up rule, and drove home after my shift last night with NO issues). Just food for thought... here's what my dad found and compiled into an email by copying EXACTLY what he found in various websites:
1. Let your TB idle for at least 20 seconds before putting it into drive. This drove me nuts, as my TB had done it from the day I purchased it. Every time I took it in for service, the dealer said "cannot duplicate condition", and sent me on my way. They replaced the alternator, cleaned and tightened all the grounds, cleaned and checked the battery connections, etc. I was finally told about the 20 second idle "fix", and it seems to work
2. "Some customers may comment that their instrument panel voltmeter is fluctuating between 12 and 14 volts on their new 2005 model year light duty full size pickup/utility vehicle.
For 2005 model year, light duty full size pickups and utilities, are equipped with a new Regulated Voltage Control (RVC) system, covered in the September 2004 TechLink. The RVC system allows changes to vehicle voltage, up or down, under various scenarios. Battery state of charge and the vehicles present electrical needs are only two of numerous conditions taken into account.
This will cause the voltmeter to fluctuate between 12 and 14 volts. By comparison, conventional systems usually maintain a more consistent reading of 14 volts.
This fluctuation with the RVC system is normal system operation and no repairs should be attempted."
3. Bulletin No.: 05-08-42-001
Date: March 07, 2005
Subject: Diagnostic Information on Headlamps Flicker or Momentarily Dim While Driving
Models:2004-2005 Buick Rainier
2002-2005 Chevrolet Trailblazer
2002-2005 GMC Envoy
2003-2004 Oldsmobile Bravada
with 4.2L Engine (VIN S -- RPO LL8)
A concern regarding headlamps flicker or become dim while driving may be easily mis-diagnosed. It is very important to capture as much information from the customer as possible. Below is a guideline to assist with diagnostics.
Verify the customers specific concern.
What time of day does this occur (is it light or dark outside) ?
What driving conditions (vehicle speed, engine speed, throttle position, etc...)?
What was the outside ambient temperature when the condition occurred?
What accessories was the driver using when this condition occurred (A/C, heated seats, rear defogger, etc...)?
If the concern is at dusk, could it be the automatic headlamps changing from DRL to Headlamp mode and possibly back to DRL again?
Are there any other relevant operating conditions?
Service Bulletin - 02-06-03-008A - Info - Low Voltage Display on IP Gauge, Lights Dim at Stop Lights, Battery Discharged, No Start, Slow Cranking, Dim Lights at Idle, Low Generator Output (SI Document ID #1540541)
Service Bulletin - 02-06-03-006B - No Start, No Crank, Battery, Batteries, Generator, Gages, SES, SIR, Brake, Security, Theft, ABS, Hot, DIC Messages, Lamp, Light, Battery and Generator Diagnostic Testing and Cadillac Roadside Service (SI Document ID #1563904)
Service Information - Exterior Lighting Systems Description and Operation (SI Document ID #826321)
Service Information - Battery Inspection/Test (Non-HP2) (SI Document ID #653410)
Service Information - Charging System Test (SI Document ID #1468059)
Service Information - Inspect for aftermarket devices that could affect the operation of the system. Refer to Checking Aftermarket Accessories in Wiring Systems (SI Document ID #816776)
Keep in mind high current draw items may cause a noticeable dimming of lights and a fluctuation in the voltmeter may be noted and is a normal operating characteristic of the vehicle.
For 2004-2005 TrailBlazer, Envoy, Rainier and Bravada with the LL8 4.2L engine only, the Secondary Air Injection (AIR) pump activation is thought to be the main contributor to this high current draw condition and is a normal operating characteristic of the vehicle. Refer to Secondary Air Injection System Description (SI Document ID #1298539).
For customers whose driving habits tend to run the AIR pump diagnostic test that leads to concerns with the headlight flickering, if the vehicle is allowed to idle for 20 seconds prior to driving, this should allow the passive test to pass and prevent from running the active test that may dim the lights. The passive test should/will usually pass 99 percent of the time, and by allowing the 20 second idle period, it should almost eliminate the active test. Be sure to check for codes and correct related concerns if this condition repeats.
Additional high current draw items are rear window defogger, HVAC blower motor, rear air suspension pump along with other components. For easier diagnostics, it may be possible to control or monitor these components with a scan tool.
It is important to inspect all related connections, grounds and battery terminals for integrity . A loose or corroded connection may exaggerate the concern, and may cause other symptoms. Refer to Testing for Intermittent Conditions and Poor Connections (SI Do
#100 of 292 Re: Oil light [rpowers]
Nov 04, 2009 (3:39 pm)
its an indicator which tells you its time for an oil change. It must be re set everytime you change the oil.
#101 of 292 Re: clock!!!! [lmgranger69]
Nov 04, 2009 (3:41 pm)
its a bad connection at the battery
#102 of 292 Re: Battery goes to 7.0 volts [bainms]
Nov 04, 2009 (3:45 pm)
I've had this 05 trailblazer almost a year to the day and haven't had this issue this bad untill tonight. Coming home on the highway it kept losing power and almost stalled out several times. In the past its done it a little but never this badly. Had the charging system tested and they said everything was fine. I'll try this 30 second idle thing but can you reply and let me know if you have anymore problems
#103 of 292 02 Trailblazer electrical/starter problems
Nov 05, 2009 (11:15 am)
I have a 2002 Trailblazer that I've been having problems with the electrical system for a couple of years. At first the emergency lights would go on when the right turn signal was activated. This only happened when it was raining or very cold. Then the dome lights started flashing on and off a couple of times. Last December the battery died and we had it replaced by a local shop, asked about the lights and he checked it out and said he couldn't find a problem with anything. He replaced the battery again in March after numerous checks. We still have the problems with the lights and battery dying. In April we decided to take it back to the dealer ship we purchased it from. They say there is no drain showing on the vehicle but that GM has a couple of notices on the ignition and rear wiper motor cause battery drains, so we have them replaced. We didn't have any more problems until late September, oddly enough when the weather started to cool and get wet. Then the car would not start when the key was turned. Nothing, no clicking, lights, radio or anything. But if I tried again it would start right up. This happened about three times in the last three weeks and we had just decide to take it back in to have it checked out when it wouldn't start at all. This was last Wednesday. We jumped it and it ran fine again. We took it in to the dealership Saturday, explained that we had it in there back in April, what we had done then and what it was doing now. They called on Tuesday and said the battery had a bad cell and that would be the reason for the battery drain. When I asked if that would cause the problem with the ignition not starting at first then starting right up on the second try she said that she didn't think so, but there was nothing about the ignition problem on the work order so he might not have checked it. I asked to talk to the manager we talked to on Saturday when we took it in. I explained to him that I was told that the problem with the electrical was a bad cell in the battery. That the tech was not even told about the ignition. He said that the ignition wasn't the problem, that the battery drain was the major concern, so there was no reason to mention that. After going around with him for awhile he let slip that the battery tested fine on Saturday but that on Monday when they checked it again the bad cell showed up. According to him there is no way that the ignition or anything they did could have caused the break down in the battery. And that it would logical that it might be a problem with the ignition again causing all our problems. But that he didn't want to replace it unless he could tell for sure and there was no way to check to see if it is bad. We are picking it up tomorrow. I didn't have the battery replaced. I'm going to have to take it to someone else. But I'm running out of options, we live in a very rural area and there are only so many repair shops around. Anyone have any ideas about what could cause the ignition to delay like it is and why would the battery suddenly go bad like it did?
I would like to have an idea about it when I take it back in.
And sorry this is so long
#104 of 292 lock problems
Nov 12, 2009 (1:36 pm)
I just had my transmission replaced in my 02 and now my keyless entry device wont work and now the trunk/hatch is permanately locked and wont open, any suggestions?
#105 of 292 please help, going krazy
Dec 07, 2009 (8:03 pm)
03 chev trlblzr, 4x4, v6. the tacometer goes dead and the truck is fine, it has no instrument lights on, nor any codes pop, the fault is intermitent. i could travel 300 miles and the tac is fine, or i drive down the block and it drops to zero, yet when i step on the gas the rpms go up to what they are suppose to read. this hasent affected any power or performance, but still am worried. i asked the dealership and all i got was dollar signs behind their eyes. i am hoping someone else has had this issue and can steer me in the right direction. i try and do all work myself on my truck, for knowledge and experience. but am desperatly seeking enlightment on this issues. if you can help you can email me at lyferikyahoo.com. thank you.
#106 of 292 Re: please help, going krazy [lyferik]
Dec 07, 2009 (10:26 pm)
you can email me at...
Let's keep the discussion here so everyone will benefit.
SUVs and Smart Shopper
#107 of 292 Re: lock problems [dilalljw]
Dec 08, 2009 (6:30 am)
You might want to take it to a place that installs alarms such as best buy or something along those lines and see if they need to reset the alarm system or the keyless hand device. That would be my suggestion because when they replace things such as the transmission they usually have to un-do the alarm and what not. I don't know to much about cars but that is where I would start.
#108 of 292 Re: please help, going krazy [lyferik]
Dec 11, 2009 (4:11 pm)
Your not alone! My wife just called me tonight while out and told me her Tach reads 7000 rpm and the oil pressure gauge reads like over 90psi. Two years or more ago the speedometer quit, and about ayear ago the fuel gauge quit! I tried countlessly to get GM to cover the speedo and they would not! So why bother repairing all this electrical if its all going to crap out like its doin. Iv been workin on my own vehicles all my life and this 2004 trailblazer is one of the worst cars i have ever driven, and have had the most electrical problems ever. When does it end! Oh yea three months ago my wifes brakes started to fade on her. After doing some investigating i found the antilock module seems to let brake fluid bleed bye therefor causing the brake pedal to fade while applying the brakes. Also had no warning light to let me know of any trouble with thw ABS system. Now i drive the car with the power disconnected to the abs system and the brakes work like preantilock systems did LOL! I never started to chase and try and fix these problem because in the end they do not affect the cars performance. I will however NEVER buy another small GM vehicle again. I own a 99 suburban with 199875 miles on it and have only done mainteance work on it. My next small vehicle will be a honda for sure, or atleast something foreign. Me being a union electrician, never thought i'd say that, but chevy has a long way to go with some of their products. If you can't tell i'm not to happy with the trailblazer. LOL ! I It is dependable but electrically leavs alot to be desired. Good luck with your quest. Let me know what you think.