In July 2005, Jennifer Matthews of San Francisco was driving with her 85-pound pit bull, Chopper, in the backseat of her five-day-old 2005 Lexus RX 330. A deer jumped in front of the car, and Matthews slammed on the brakes. Chopper flew forward; a front paw hit the windshield and his back paws went through the LED screen of the navigation system. The damage was caused by an accident, and therefore it wasn’t covered under warranty. The cost to replace the navigation system: $6,600.

In today’s high-tech automotive industry, computers and sensors are rapidly replacing mechanical parts, increasing vehicle safety. But this additional convenience can bring frustration and debt. Consumers aren’t buying sparkplugs or gaskets or even plain metal keys anymore. Some of the newer, hot vehicle options include rearview cameras, adaptive cruise control, radar sensors that slow you down if you get too close to the car in front of you and keyless entry — all electronic, and all very expensive.

Multiple airbags are now common, and not just in luxury or even near-luxury vehicles. No one would argue against airbags, one of the most important safety features in a vehicle, and sensors (essentially computer chips) have made them even more effective.

But, did you ever wonder what happens when all those airbags deploy? In such an event, your insurance company may deem your vehicle a total loss.

“If you take the damage to a vehicle, plus the deployment of airbags, it does have an impact on totaling,” said Mike Siemienas, an Allstate insurance spokesman. “With the addition in the early ’90s of dual front airbags, the likelihood of totaling a vehicle increased. But, you have to have significant damage to have a total loss.”

Yet, some aspects about vehicles haven’t changed: Sheet metal still envelops us, tires still connect us to the road and engines are still aluminum or cast iron. However, when you hear phrases like “drive-by-wire” — which controls the car’s operation and can react to emergencies faster than a human driver could — you know a mechanical part has been replaced with technology.

We can connect to 911 without a cell phone, global positioning systems know where we are and where we want to go, cameras tell us it’s OK to back up, warning systems let us know if we can change lanes and video screens entertain us. These new levels of comfort and connectivity, which were unimaginable 10 years ago, are expected by today’s consumers. But when things break, the cost to repair them often stuns owners. Sure, your insurance company may cover the repair, but they won’t forget you made a claim.

“People who are optioning their new vehicles are so focused on the latest technologies, they never think about what it would cost to repair or replace that item,” said Kim Hazelbaker, senior vice president of the Highway Loss Data Institute. “The average amount of any insurance claim today is $4,000 on top of a deductible. Replacing a rear camera, for example, is $4,000. With a $500 deductible, that raises the cost to $4,500.”

According to the Highway Loss Data Institute, expensive items to replace include: Xenon headlights with washers, $1,600; adaptive cruise-control components, $1,300 to $3,700; adaptive headlights with washers, $2,000; power-heated turn-signal side mirrors, $443 to nearly $1,000; back-up cameras, $4,200; and rear-parking assists, $900. These prices do not include the cost of labor.

“Technology is expensive,” said Tony Molla, vice president of communications at the National Institute for Automotive Service Excellence, which has a certification program for independent service professionals.

“My daughter wanted an iPod for Christmas,” he said. “It cost $400. A Pentium processor microchip costs $1,200 to $1,500. The same costs apply to automotive technology. Generally these parts are made to last the life of a vehicle, unless there’s an accident.”

That’s the good news. If any electronic system fails under warranty — and they do from time to time — they are replaced by the dealer. Warranties are getting longer, sometimes covering up to five years, and everyone has car insurance that covers most damage caused by accidents. But there may be a big deductible, and if the claim is big enough, you can be certain your rates are going to escalate.

Car buyers probably won’t option less now because they could get slammed with a $6,000 repair bill sometime in the distant future — no one buys cars that way. But knowing there’s a risk for sticker shock on a repair helps evaluate the true cost to own and operate a vehicle.

Extended warranties will include some vehicle systems that aren’t often covered, such as navigation and telephone systems. Depending on how long you own the vehicle, it can be a good idea to have such protection even after the manufacturer’s warranty expires. But thoroughly check the reputation of any extended-warranty company you do business with — some have a way of going out of business and leaving customers with a worthless warranty.

The cost of an extended warranty is lower when the vehicle is new. As the vehicle ages, the cost of the coverage goes up, but a fixed rate will cover whatever goes wrong.

Although warranties can protect you in the event that something goes wrong, the best way to take care of your vehicle’s technology is to keep it clean.

"The best way to avoid costly repairs on electronics is to follow the manufacturer's maintenance schedule,” Molla said. “The beauty of electronics is that there are very few moving parts, so they are much simpler than mechanical parts. If you keep your vehicle clean and adhere to the maintenance schedule with regular oil changes or whatever the manufacturer suggests, any good technician will notice any corrosion on connectors to electronic sensors. All they do is clean them off, probably without even mentioning it to the customer.”

Other than an extended warranty, Molla said regular maintenance is about the only thing consumers can do to avoid paying out of pocket for costly repairs.

“It's like taking care of your health — if you let things go, they get worse,” he said. “If your connectors aren't cleaned off, corrosion will get worse and you'll have a short circuit. Then a lot of things will get fried and you'll have a big repair bill.”

A Pentium processor microchip costs $1,200 to $1,500.