Chevy Trailblazer

The Chevy Trailblazer is a sport utility vehicle (SUV) manufactured by Chevrolet. It was launched in 2002 as successor to the Chevrolet Blazer. This model won the North American Truck of the Year award in 2002.

5,837 Questions
Oxygen Sensors
Chevy Trucks and SUVs
Chevy Trailblazer

How do you cleaning oxygen sensor Chevy Trailblazer?

I cleaned one once,fully expecting to have to buy a new one, with a very fine wire brush and or steel wool and a little wax and grease remover on a rag. Ididn'thave to buy a new one. the check engine light went out and it ran fine. Hope this helps.

Headlights Tail and Brake Lights
Pontiac Grand Am
Chevy Trailblazer
Grand Am GT

How do you change the high-low beam headlight bulb on a 1999 Grand Am GT?

remove the ram air cover under hood. there are 2 L shaped brackets that hold each headlight in car. lift / pry these out using pliers to gain access to rear of headlight.

Chevy Silverado
Chevy Trucks and SUVs
Chevy Trailblazer

How much horsepower does a Chevy Trailblazer have?

6 cyl has 265-280

Cars & Vehicles
Chevy Blazer
Ford F-150
Chevy Trailblazer

Why would the engine while accelerating bog down and loose power then regain all the power at once?

If your car is fuel injected, the electronic throttle position sensor on the throttle body could be bad. The check engine light doesn't always come on, in this situation.


Well it kind of depends on how new the car is. If it's a newer one or your lights start to go dim as one person put it, it is quite simply the governor. Fairly cheap and easy to have that problem fixed. If it's an older vehicle read some of the answers below, they're pretty accurate, although one other thing it could be is a blocked catalytic converter.


I had the same problem with my van, after many misdiagnosed repairs it turned out to be that the 02 censor was not working properly, have that checked.


I surprised myself and resolved this problem on mine: Too much dirt, etc built up in in line fuel filter. As I accelerated larger demand for fuel caused blockage and starved off motor.

Check the little things first!


I have the same problem but not the answer.

But I have just realized that when it happens the driving lights go dim.

Bog When AcceleratingI had this same problem with my 1988 Chevy S10 Blazer 4.3L This could be a problem with your EGR circuit. This circuit stand for exhaust gas recirculation and is responsible for moving a little exhaust gas back into the engine for combustion. If your vehicle is newer than 1973 it is required to have this device in it because it reduces NO2 emissions. Replace the EGR valve and solenoid (valve first because it is more likely to be the issue). They are both fairly inexpensive parts (mine was about $110 for both) and they are easy to replace. You don't even need a mechanic for this fix. If you try this and it doesn't work, put your old parts back on, return the new ones and try replacing the throttle position sensor if you have a fuel injected model. Hope this helps.

That all depends if its a carbureted model or a fuel injected model. Carbureted model has an easy answer. You have a dead spot in the carb. you can do 1 of 2 things. Rebuild your old carb or buy a new one. Generally the float is just sticking. With fuel injected cars when you have a problem like that the check engine light should come on.

If it has a distributor, check to see that the weights under the rotor are free moving. If they stick, then the timing will be slow to advance and the engine will bog for a second or two.



Any of the above could be true. It also could be carbon build up in the intake lines, valves, & carb (if there is one.) If this is the case, a fuel intake cleaner will clear it out and a new fuel filter will also help. Carbon does the same thing to those components as cholesterol does in your arteries.

Good luck!

Just had this problem with a 350z. The car was cutting off at 5k rpms, then gradually got worst and started cutting off at 2500 rpms. Turned out it was a bad MAF sensor. I replaced mine at a very costly price! I would suggest (If applicable), clean your MAF sensor. You can buy the cleaner at autozone. Doesnt hurt to try!

Cars & Vehicles
Auto Parts and Repairs
Honda Accord
Chevy Trailblazer

How do you fix a car's dash vents if they do not seem to work?

My husband and I fixed ours on a 1985 Toyota corolla. There is a blower motor which was located under/ behind glove compartment, we bought a used one from a junk yard switched then and we had our vents back.

Cars & Vehicles
Chevy Suburban
Chevy Trailblazer

How do you remove a u-haul trailer hitch?

the u haul hitch is stuck on there good the only realistic way to get it off is with a pneumatic impact wrench orelse your just going to snap the torque wrench heads even a brake bar will bend the neck
Chevy Trailblazer

Do trailblazer ss rims fit on trailblazer ls?

Yes, Chevy Trailblazer SS rims will fit on a Chevy Trailblazer LS.

Chevy Trailblazer

How do you remove Chevy Trailblazer CD and radio from dash?

trying to wire pioneer stereo in 2002 trailblazer

Chevy Trailblazer

Does a 2006 Chevy Trailblazer have shocks or struts?

A 2006 trailblazer has 2 struts in the front and 2 shocks in the rear

Chevy Trailblazer

P0014 diagnostic code in Chevy Trailblazer 2002?

" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1)

Hard starts
poor idle

wrong camshaft timing
Wiring issues (harness/wiring) in intake timing control valve control solenoid system
Steady oil flow to VCT piston chamber
Faulty timing valve control solenoid (stuck open)

The fix
Replace the VCT unit or one of its components

Mazda 929
Toyota Highlander
Timing Belts and Chains
Chevy Trailblazer

How do you change a timing belt on a Mazda 626 1999 6 cylinder?

the easiest way to change the timing belt is to remove the grill, center section of the radiator support, and the radiator and fans. Leave the airconditioner condesor there, it would be more difficult to remove. Once all that has been removed you then have to remove the blelts, the tensioner (completely) and the crack pully. then you have access to the timing chain cover, which you then remove and there it is. A tip when replacing the belt is to also replace the water pump since you already went through the trouble. I just did all this yesterday and the water pump cost 39.99 and belt was 35.00.

Answer1. slow percausion 2. use a menual step by step 3.starting with cam pully your way in and out 5. ) AnswerNot to be rude, but if you have to ask, you need take it in.

A TB is a project for someone with a good mechanical aptitude (and most likely, a shop manual), it is not just a simple fix, like a bulb or radio, etc. If you do it wrong, you'll likely leak coolant, or worse, total the engine.

Most newer engines are 'interference engines' meaning a timing belt that breaks, slips or has some other sort of misalignment causes physical (costly) damage to the engine's internals.

Usually, it is the valves that get bent, which entails about a $750 repair (in addition to the cost of the belt repair). Worse, a piston or cylinder wall gets cracked, which usually means a new engine, that can become a $2000 expense real quick.

Dealers are expensive, usually 30% more than independent shops on a timing belt.

Find a good local independent shop and consult with them, you will likely spend about $150-$200 in parts, and another $300-$400 in labor. Not cheap, but a lot better then the alternative.

HTH, Mark


Not to be a prick.. but the dude (Mark) that answered above me most likely works for a mechanic shop. I have rebuilt 4 engines and have done it all by trial and error. Ask questions and/or grab a Chilton manual. The best way to save money is to do it yourself. Just keep an eye on what you are doing and be sure to mark what you disconnect so you don't forget where anything goes. EASY AS PIE!!

Car Sounds
Chevy Trailblazer

What would cause a whining noise while accelerating?

Whining noises often come from the alternator or the steering pump. Check the power steering fluid in the pump (there is a dipstick on the pump), and have an AVR test done on the alternator.

If the alternator is faulty, you are probably having battery problems as well. If the steering pump is low on fluid or is faulty, you probably are experiencing jerky steering from time to time.

Serpentine Belts
Chevy Trailblazer
1995-2005 Chevy Cavaliers

How do you release the automatic tensioner to change the serpentine belt on a 1991 Chevy S-10 4.3 liter V-6 engine?

i had the same exact vehicle. you don't release the tensioner, you'll have to take the presure off with a ratchet and socket. on the front of the tensioner pulley there is an arrow that has "loosen" next to it . get a socket that fits on the bolt in the middle of the pulley. ratchet the pulley towards the loosen side. there will be alot of tension so be careful. the belt will loosen when you turn it. slip the belt off the pulley and very slowly release the pressure off. it will pull against you alot but it will stop. just reverse this when putting the belt back on. also try to not take all the belt off if you don't have to, this will help w/putting the belt back on.

Dodge Dakota
Chevy Trailblazer

Where is the drain plug for the radiator in a 2000 Dodge Dakota?

I think its at the very bottom right hand corner of the radiator. It is a small plug looking jobber. Access is very very tight. Basically, lift the hood, take a flashlight and look along the drivers side of the radiator at the bottom. You'll find it right below a small nipple looking jobber.


That's pretty much where mine is on my '02, but I have a small & short hose that connects right above and below it. I disconnected both ends of the hose to gain access to the drain plug for the duration of the radiator drain without ill effect.

Ford Explorer
Chevy Trailblazer
1995-2005 Chevy Cavaliers

Where is the headlamp relay switch located on a 94 Ford Explorer diagram does not indicate headlamp?

the headlight on my ford explorer keep going on and off on it does not go off on the dashbroad i want to no what it is

Chevy Corvette
Daewoo Nubira
Timing Belts and Chains
Chevy Trailblazer

How do you change the timing belt in a 2001 Daewoo Nubira? Has all the parts for the Nubira of all years and the books on how to do it.hey buddy, sorry to break it to you but theres no timing marks,and you cant get a book for the car.The company went out of business. Theres a possibility the valves were damaged when the belt broke. If its double over head cam then you point the dots on the sprockets straight up or look on the valve cover for the two dots. And line them up,as for the crank- shaft I'm guessing theres no marks to line up so your gonna have to set the number one cylinder to top dead center. you can get another head at a junkyard if the other one is ruined. good luck buddy..

I just finished changing mine in a '99 Nubira. I have the DOHC and both cam gears are labeled with intake and exhaust marks. It's supposed to make the gears interchangeable, but it just adds to the confusion if you're not sure which one is which. With mine the exhaust is on the right, and the intake is on the left. As far as the crank goes, there is a mark on the crank that you line up with the bottom of the timing cover. It's not labeled very well. Mine looked like a square notch about an eighth inch deep that I had to line up. In theory, if you line up all these marks correctly everything should line up. One thing to keep in mind, if your engine is an interferance engine you probably at least bent some valves when the belt broke. I can't tell you how to tell if your's is or not. Mine is.

A copy of the factory repair manual is available online at, You can download it free as a PDF file, it was a real lifesaver for me when my timing belt broke and bent all the valves.

You can get the book and all the parts for your car at

Heater Cores and Blower Fans
Jeep Grand Cherokee Limited
Car Heaters
Chevy Trailblazer

How do you repair a 2002 Jeep Grand Cherokee dual climate control that blows cold on on one side and hot air on the other when the heater is running?

There are several things that can cause this problem with Jeep Grand Cherokees. The actuator (door motor) can cause this, the door could also be broken. There is an good article that goes into more detail - the link is at the bottom of this page. Often, the actuator motors are too strong for the plastic doors, and they break over time. The typical fix involves removing the entire dash and replacing the plenum assembly. There is a DIY kit by heatertreater that provides instructions on how to perform the repair without removing the dash.

I just started experiencing this same exact issue with my 2002 Jeep Grand Cherokee Limited on a road trip yesterday! It works as it should on the driver's side, but only blows cold air on the passenger side regardless of what temperature you set it on! Also, even if I completely close the passenger vents, some cold air still comes out from them and also from the floor area!

I had the same problem! Here is my cheap quick fix. Remove the glove box lid, there are 2 rubber retainers that hold it in place, just pull them out they are easy to put back, the lid will now drop down to reveal the the door motor housing, disconnect the electrical lead(Make sure you remove the neg lead on the battery first)Undo the 2 screws and then pull out the motor. A new motor cost me approx 100 pounds. If you do take my approach make sure you test the motor before you buy new as it could be some other problem. Once you have removed the motor it's easy to open and close the door by it's spigot, just to make sure it's not stuck in any way. My final test was to check for power to the electrical lead. Reconnect the battery. While turning the temp conrol check with a meter to see if there is power to the lead.

It sounds like you have aq problem with the right temperature door assembly. I have a similar problem with my 1999 Grand Cherokee Limited, but, in my case, the unit just blows cold air. The question is: How do you access these door assemblies to change them? Help! I am a do-it-yourself person and want to know where I can locate information about how to access the AZC system door assemblies to change them? I understand it involves removing the entire dash board in order to get access to the passenger side one that is broken. To do so I need some type of repair manual.

All I know is I have the EXACT same problem with by 99 jeep grand Cherokee. It started with one side blowing cold and the other blowing hot. Now, both blow only cold air. I took it to the dealer and they wanted to charge me $800 to fix it stating it was some switch that has been going out in all jeeps this model with dual heating system yet they would not consider it under warranty as a issue. Hence, I still have no heat.

I just had the problem on my 01' jeep grand the dealer told me it was a bad bun door and actuator on the passenger side at a charge of $1200.00. If your good with cars you can do the job yourself and I mean good this job was a pain in the butt the dealer est. 12hrs (plus u need to disc. the heater core and evap. for the ac) of their time it took me exactly that. Once I got the HVAC system out of the truck I noticed since the car is temp. control zoned the passenger Sid bun door which controls the flow of heat to the passenger vents was broke. The dealer was aware of the problem picked up a new part for $200 and slapped it back together worked fine( the actuator was not bad it just doesnt respond to a broken door so don't let them sell you one, you should only need a new bun door)


The problem is a wear out mechanism with the blend doors. The doors break and are stuck in the AC position...NO HEAT. There is a new product that solves the problem. Search on Google for "heatertreater" for a complete explanation of the problem and a solution.

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The problem with the system is the design of the actuators. The failure of this so called" bun" door is due to the poor design of these actuators. Over torque and excessive wear leads to failure....The only way to resolve this problem is by replacing both actuators and the temperature blend door assembly. Do not just replace the door!!!! ( note: fresh air door has same problem) I average one grand Cherokee a week in my Cooling systems repair shop. 675.00 is my going rate. It pays 6.1 hours and nothing more...don't be robbed by the dealership and stay away from driveway mechanics. Beware that your entire instrument panel must be removed along with the evacuation of the refridgerant. Not a "do-it-yourself" deal! Good luck and never by a Jeep again!

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Your failure description is the classic fail description for broken blend doors, and this is a common problem on the GC. There is an inexpensive DIY kit on Ebay from heater treater that will fix the problems without having to remove the dash panel.

The HVAC system is computer controlled and when the doors break, the computer senses that the movement of the doors is out of spec and shuts the motor down. Actually it is rare for the actuator motor itself to go bad. Usually it's a broken door combined with computer control. You can check the motor with a 9V battery and a snap connector. Just touch the wires to the motor terminals and check that it turns.

Another Example

I just thought that I'd add my experience: I have a 1999 Jeep Grand Cherokee Limited 6-Cyl. About a year ago heat went out on passenger side (cold air came out on passenger side when heat was on and coming out on driver's side). Spring and Summer came, so I forgot about it. This Fall (maybe 1-2 months ago) I was reminded of the problem when the cold air came back. Now, about 1-2 weeks ago, all blower functionality is gone ... a real problem if you need to defrost the windows! I'm going to try the AZC test and look into the HeaterTreater. I'd hate to put any more big money into this vehicle as it has been a true money pit. I'll never buy another Jeep. It's a classy ride, but I've put more money into repairs for this vehicle than any other two vehicles I've owned.

Easy fix is available

There is a video available that shows the complete repair process and goes into an explanation of the root cause of the problem and the solution. You can also find the video by searching on YouTube. This is a very common problem on the Grand Cherokee and the kit gives a simple effective fix for the problem and is much much cheaper than taking it to the dealer.

Assuming you are going to replace the 99/04 Jeep Grand Cherokee blend doors yourself.

You would start by disconnecting the negative battery cable.

If you are going to remove the dashboard, etc to replace the blend doors.

some websites give you complete instructions with plenty of pictures.

It will take the average person with little or no auto repair skills approximately 12 to 16 hrs.

The vehicle will have to be taken to a shop that can recover the refrigerant before you start removing the dashboard and HVAC box..

If you are going to do the type of repair where you cut an access hole in the side of the HVAC box.

A short version of how the access hole repair is done.

Disconnect the Negative battery cable.

Lower the glove box

Remove the actuator motor - You will need a Phillips screw driver

Cut an access hole in the plastic HVAC box - Use a multi-purpose cutting bit, you will need a rotary type of cutting tool, like a Dremel, RotoZip, etc. Or you could do the cutting by hand with any type of small cutting tool, it will just take longer doing it by hand. Or some people have used a narrow pointed soldering iron!

Remove the broken blend doors

Install the new Blen Dor dual control blend doors.

Replace the actuator motor.

Close the access hole - Replace the wall piece of plastic you cutout -Use foam tape or an aluminum tape to cover the groove made by cutting the wall.

Close the glove box.

It is almost as easy as what you just read, the hardest and the most time consuming thing to do is cut the access hole.

The job should take between 30 minutes to 1 ½ hours. Depending on how long it takes you to gather your tools, etc.

Before you do anything major find you hvac fuse, pull it, then put it back. It might be in the fuse box under the hood or the one inside. All mine needs is to cut the power to the havc unit then it resets.

Spark Plugs and Wires
Ford Explorer
Chevy Trailblazer

How do you remove a broken sparkplug?

um this should be left to a pro stricklly because the plug hole will need to be re- threaded and the piston must stay free of deposits during this period but if your workin on the old mower try an extractor set a good on not no wal-mart junk go to sears or depot

Car Sounds
Saturn S-Series
Chevy Trailblazer
Ford Escort ZX2

What would cause a loud whining noise in a 2001 Saturn SC1?

timing belt

AnswerI wouldn't think it would be the timing belt. In fact I thought (although I might be wrong) that most Saturns have steel timing chains.

I would suspect the noise is either the power steering pump or one of the serpentine belt tensioners.

In fact I had a loud whining in my 2000 Saturn and it was the bearing in the serpentine belt tensioner. We replaced it ourselves, it was not too bad of a job.

AnswerIf the noise sounds like a jet engine turbine, it's probably the alternator getting ready to self-destruct. Check it by running the car and turning accessories (headlights,radio,wipers,etc.)on in sucession. If the noise gets louder with each accessory you add, think alternator. Answer(Former Saturn Service technician) I would say that if it't a high pitched whine that varies with engine speed, it is most likely the alternator. A lower pitched "whine" or "growling" might be the serp. belt Idler Pulley. In my experience, I never saw or heard of the tensioner pulley bearing faliing so most likely rule that out. A bad tensioner usually makes a "rattling" type sound and is accompanied with belt "squeal" AnswerMy loud whining noise in my 97 Saturn SL2 WAS my Idler Pulley! I replaced it for around $23 at O'Reilly Auto Parts, but the original owner said that it was making that noise when she bought it brand new from Memphis Saturn, so apparently this was a defect from the factory. Anyhow, it is now fixed and I can drive around without going crazy!


I have a 96 sc2 it wined like it was a power steering pump but it was the idler pulley. To find out if that is the issue is to grab all the pulleys one at a time and see if they are tight or not. Good luck it only cost $20 dollars for the idler puolly and that fixed my problem.

Chevy Trailblazer
1995-2005 Chevy Cavaliers
Chevy Colorado

How do you calibrate the compass on a 2005 Chevrolet?

In most cases you press the reset button on the compass and then drive in circles (in a parking lot) while it calibrates.

Ford Ranger
Ford F-150
Chevy Trailblazer

How do you change the lower ball joints on a 2001 Ford Ranger 2WD extended cab pickup?

I may not remember this correctly but.... the ball joints on the Ford need to be pressed out. You can smack them out with a hammer but they must be pressed in. With a lot of Fords you must remove break pads and the entire spindle. 1. Pull cotter pins and loosen nuts on upper and lower ball joints as well as tie rod. Leave nut on end of thread. Smack with hammer until loose. Make sure the hit is metal to metal. 2. Remove spindle and put in vice. Press or use hammer to knock out ball joint. 3. Lube opening (Non-seize) before pressing in new ball joint. Ball joint must go in straight. 4. Replace There is a special tool made for removing and installing ball joints. It's called something like a "C-frame assembly tool". I know of one autoparts store that has a loaner program that will loan the tool. But most autoparts stores don't. It helps if you have a forked tie rod end remover to break the tie rod loose.

Car Electronics and Lights
Headlights Tail and Brake Lights
Subaru Impreza
Chevy Trailblazer

If your lowbeam headlights do not work but your highbeam functions fine where do you troubleshoot?

I have the answer to your question about troubleshooting your headlights on your vehicle. I would isolate the wire that comes from the headlight switch to the headlamp bulbs for low beam and check to see if there is a short in the wire. You can find this wire by using a test light turn on the key and get a good ground with the test light poke the wire and see if the test light illunimates with the headlight switch on. Good luck!

check the wires, and check the fuse for your lowbeams. could of blown a fuse on your lows, but your highs will still work.

Every single time I have had a failure of low beam in a headlight without failure of high beam, it has been because the lamp bulb or halogen lamp module has reached the end of its serviceable life, not because of any wiring problems. Low beam burns out first because it is on the most. If low beam is lost simultaneously in both headlights, I would check fuse first, then the headlight switch. If low beam is lost on one side only, it is almost always going to be due to the bulb or lamp module needing to be replaced. In that case, replace them in both headlights because the other one will be going kaput in short order, as well.

ya i second that notion -anonymous feb '05


Measure for voltage at the light bulb clip first. It could be a bad set of bulbs. If you have no voltage, check fuses, and then check for voltage before the headlight switch. It could be a faulty headlight switch. Measuring a few voltages will tell you what the problem is.

Change the headlight bulb. 99% of the time it is the bulb that is the problem.

Most definitely check out the headlight dimmer control switch .... Ron J.

the lamp is probably bad easy to check look at it. hi beam light do carry more current and tend to fail sooner

Spark Plugs and Wires
Chevy Silverado
Chevy Trailblazer

How do you get rid of spark knock on a 2003 Trailblazer?

The problem is related to a computer componet. It could be the crank position, engine speed, or any other sensor. The only real way to determine the problem is to use a diagnostic computer, and those could get quite pricy(1000's to 100000's thosands of dolars). A 2003 model should still be covered by the warranty. So, bring it to your dealer. what ever your deductible is should be the only charge check your contract the deductibles run from $0 to $250 the last time I checked. Also, there may be a hidden warranty, technical service buletin(TSB), or a recall that relates to your specific problem. These are available through General Motors and dealers should have access to them. If they do not gladly give you a copy call Chevy direct. Their contact info is Chevrolet Motor Division, General Motors Division of General Motors 100 Renaissance Center Detroit, MI 48265-1000 800-222-1020

could be cheap fuel or a non-working EGR valve

Chevy Trailblazer
Dieting and Weight Loss
Remote Control Devices
Sony Playstation 3

Where did control-trim come from?

Developed in 1995 and patented in 1998, it was originally licensed by FiberGels Technologies, Inc., and more recently was acquired by Circle Group Internet, Inc., of Mundelein, Illinois. Created by the USDA from crop-processing byproducts, such as oat, soybean, or rice hulls, it is a natural food product that is being marketed as Z-trim. The techonolocy has also been marketed under different names such as LA Weight Loss's Controltrim.

Chevy S-10
Chevy Trailblazer

Where is the speed sensor on a Chevy S-10 Blazer 4-wheel drive with overdrive?

on the tail shaft of the transfer case does this sensor on the tail shaft screw in with the plug on the end of it, or does this sensor have a bracket that bolts on? On all Chevy's there are 4, one on each wheel(if its 4 wheel disc) Only on Fronts brakes if you have rear drums there are no speed sensors.

They can be found on the hubs, behind the rotors. As they read wheel speed through a magnetic field produced by a magnet on the hub guaging off a notched metal ring on the front drive shafts or inner side of rotors. The VSS or Variable Speed Sensor, is an Electrical pulse sensor that sends a signal to the DRAC (Digital Ratio Adapter Control) informing it of the vehicles speed. From there signals are sent to the Power Train Control Module, and to the Cruise Control. If your Speedometer is not working, 99% of the time its caused by a defective VSS. On 2WD models, the VSS is located on the tailshaft of the Transmission, drivers side. On 4WD models, the VSS is located on the tailshaft of the Transfer Case, drivers side. You will need a 1" socket to remove the sensor. The ABS Wheel Sensors are NOT related to Speedometer issues. And NOT ALL Chevys S-10 models have ABS (Anti Brakeing System), at least my 1991 S-10 Blazer 4WD does not. The ABS Wheel Sensors only apply to models that have an ABS system. The ABS wheel sensors simply supply information about individual wheel speed to the ABS control module for braking control. Anti-lock brakes are designed to prevent skidding and help drivers maintain steering control during an emergency stopping situation.


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