Which parts fail
Components named in complaints (battery, alternator, wiring, ignition, instrument cluster, infotainment).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2003 Chevrolet Avalanche 1500 owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl* the contact owns a 2003 Chevrolet Avalanche 1500. While driving 60 MPH, the vehicle failed to accelerate. The instrument panel gauges fluctuated independently and several warning indicators illuminated. The vehicle also stalled. The contact was able to restart the vehicle, but the failure recurred multiple times. The vehicle was taken to an independent mechanic who diagnosed that the vehicle had electrical issues. The vehicle was not repaired. The manufacturer was not made aware of the issue. The approximate failure mileage was 230,000.
I am a new owner of a 2003 Avalanche, I was satisfied with my purchase but my soonroof falls under the appropriate serial numbers (6,000,000-6,300,000) recall states that it May be covered by the company webasto hollandia. Vehicle is fine to drive places but sunroof must be fixed for coming winter. It worries me as there's a slight danger of it causing a road hazard if it were to fall out.
My 2003 Chevy Avalanche has a known defect with the instrument cluster. All gauges on the vehicle can stop functioning without notice. This results in the driver begin unable to see the vehicles speed or any other information about the vehicle including what gear the vehicle is in or even whether the vehicle is in "park". In my case the gauges failed during a snow storm in colorado, which made difficult driving conditions much more dangerous. This is a serious safety issue which could result in both injury and property damage. Apart from the obvious issue of not seeing essential vehicle information, drivers could inadvertently put their vehicle in the wrong gear such as reverse rather than park. GM acknowledges that this is a know defect with these vehicles but refuses to correct it unless the vehicle has less than 70,000 miles. …
My 2003 Chevy Avalanche z-66 has just now developed speedometer problems and I am sorry it is a safety issue and concern but general motors has brushed it off as no case closed. My speedometer started acting weird,it only works for short distance driving then either shows last speed obtained or zero. My example for GM is this: no other GM vehicle I purchase ever had this problem and even though you May not think of it as a safety issue perhaps you might rethink this thought by getting into a vehicle where the speedometer sporadically works then stops working all together while you are driving. …
I was driving approximately 15 to 20 MPH down a hill that was curvy and all of a sudden my truck completely shuts off as I was driving down the hill and almost went into a ditch because the truck just shut off while in drive and luckily I was quick enough to put it in neutral so I could steer it away from the ditch and I turned the ignition over and luckily it turned on while in neutral otherwise I would of crashed into the ditch. Then it shut off again about 30 seconds after and luckily I was able to put it in neutral again so I could steer and coast down the hill because it wouldn't start up the second time when it all shut off. I was stranded at the bottom of the hill near a light so I tried to start it again and it would keep trying to turn over but wouldn't start again. I was stranded in the middle of the road and had to call aaa to tow my Avalanche to my house. …
Speedometer failure on 03 Chevy Avalanche. Apparently there was a lawsuit against GM because they used inferior parts within the instrument cluster that are prone to fail. They have since settled the suit in late 2007 and agreed to fix all vehicles with less than 70K miles. However, what about the rest of us with more than 70K miles that are driving without a speedometer because GM is charging $500 to repair the most important instrument in the car, the one that should last the life of the vehicle according to the lawsuit...... I've even gone so far as to try to find the parts for the speedometer, but they are not available. You have to purchase the entire instrument cluster as a unit. If that is not enough, I can purchase the cluster for $275 and install it myself, but the unit has to be programmed to the vehicle in order to work. This programming will cost $150.00 by the dealership. …
I bought this vehicle and the cluster is out I do not know what model this is other than a z66 so I cannot see on how to program my phone at to the OnStar or any of that I don't know if I have satellite radio there is no auxiliary plug in heated seats it's only the back of the seat that works I'm not sure if that's all that is heated and it says that it's supposed to be come with a key fob I did not receive my car completely dies I have to turn it completely off turn the key around and started again the whole steering column looks like it has been replaced I did not receive the key fob I cannot lock the doors because the keys don't work in the door but they do an ignition sometimes I have to turn the key around sometimes even when I'm in the middle of driving I have to cut it completely off because it will stall out turn key around and it start it again. …
I have a 2003 Chevrolet Avalanche that I purchased new from the dealer. It has approximately 104,000 miles on it. The problem is that my speedometer is acting erratically. Some times it will say I am doing 120 MPH on the highway or city street and sometimes it will not move at all. When I turn off my vehicle, it is often stuck at some speed such as 65mph. I can hear a physical grinding noise in the speedometer itself. This does not seem to adversely affect the odometer. I cannot reliably tell what speed I'm going, and my vehicle will not pass the texas state inspection with this problem. I contacted the dealer, and was told by the service advisor that this was extremely common, but that there is no recall. They said it will cost over 500.00 to fix this problem. I researched it on the internet and found literally hundreds of cases of this exact same problem. …
Speedometer displays erroneous speeds. Most of the time less than what the vehicle is actually traveling which creates a public safety hazard. There is no indication to the driver of a problem. All other indications are normal. It was not until a GPS with speed indicating capability was installed in the vehicle that the erroneous speedometer indication was known. Further investigation reveals the speedometer operates correctly until the dash/instrument panel heats up. At this point the indicated speed can gradually vary, sometimes drastically from actual vehicle speed unknowing to the driver. …
At approximately 91K miles the speedometer began to intermittently fail, then at approx. 96K miles, the tachometer began having the same issues. I've noticed on multiple bulletins where hundreds to thousands of people are having this same issue and we're all curious to know why GM has not been instructed to issue a recall. GM has stated (via customer service reps) that knowing your speed is not a safety concern. I pose the question then, why do we have speed limits? Of course your speed is a very important safety concern or it wouldn't be regulated. They need to replace these defective products they've put on the road & reimburse those that have already paid to have the repairs completed. …
Electrical complaints in other Avalanche 1500 years
Frequently asked questions
How common are electrical problems on the 2003 Chevrolet Avalanche 1500?
NHTSA has 84 complaints about the electrical system of the 2003 Chevrolet Avalanche 1500, 46% of the model year's 182 complaints. The component named most often is instrument cluster/panel (47 mentions).
Is there a recall for 2003 Chevrolet Avalanche 1500 electrical problems?
No. NHTSA lists no electrical system recall for the 2003 Chevrolet Avalanche 1500. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2003 Chevrolet Avalanche 1500 electrical problems start?
Half of the complaints with a recorded mileage happened before about 85,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 0 injuries to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.