Re: Mahindra XUV500 : Test Drive & Review Should I be concerned about too much electronics in my car?
It’s impossible to buy an automobile these days that has no electronics in it. Usage of electronics range widely based on segment, manufacturer, price, features, comfort, safety, etc. What exactly instigated this write-up? I booked an XUV W8 FWD for its value-for-money before even I took a test drive, but my mind started to take over soon after. The first thought that came to mind after the test drive was the possibility of electronic failure. Since the Electronics was my biggest concern, I attempted to quantify Reliability concerns (please allow me to caution you upfront that I made quite a few assumptions in my analysis and some of them could be way off – but it’s an honest attempt to convince myself).
Quality - How well a product conforms to its rated specs at time zero.
Reliability - How well a product conforms to its rated specs over time (Quality over time).
Usually manufacturers’ warranty covers Quality related issues. What if I’m provided 3 years / unlimited km warranty? What if the initial niggles are being sorted out at a rapid pace? It’s a very good reactive approach, but how about testing them in the first place before the product leaves the plant (proactive measure)? Looking at number of initial complaints posted here, one would wonder if the electronics are tested in the production line at all! While these niggles are pain value, by itself it shouldn’t be a deal breaker. Quality related issues surface typically in the first few months and they get fixed as part of warranty any way (It’s just pain value going to ASC).
What about reliability? Usually reliability of electronic components (semiconductor ICs) is specified in FIT rate(number of failures per billion hours). The failure rate follows what is known as a ‘bathtub’ curve. It simply means, the failure rate is high in the beginning and quickly comes down in the initial usage period stays constant for the next several years and finally goes up steeply towards the end of product life cycle. In plain English, if an electronic component works well in the first few months, then it continues to work well for many years without problems. Most of the tier-1 electronic component suppliers provide less than 10 FIT rate on their latest technology products. Assuming that the vehicle has about 40 electronic components (taking a ‘wild’ guess) and assuming 100 FIT rate (conservative estimate), the probability of an electronic component failure after 5 years is 0.66% and after 10 years is 1.32% !!! In other words, there is about 1 in 150 chance that you will replace an electronic component after 5 years. Is it so bad? Just like one needs to change consumables, tires, brake pads, clutch pads, etc during the course of automobile life, the electronic component replacement can also be added in. However the purpose of this calculation is to highlight the probability of any such replacement. You are welcome to play around with the reliability calculator to find out reliability trends (see attached xls file).
Is W8 worse than W6 when comes to Failure due to Electronics? If I assume 10 ‘extra’ electronic components in W8 version as compared to W6 version, then the actual probability of an electronic component replacement after 5 years goes up from 0.66% to 0.83%. So, the risks associated with electronic component replacement in W8 is not significantly higher than W6. But if you weigh in the safety features (ESP) of W8, the fractional drop in the reliability may be well worth it (at least in my view).
With all due respect, if the experts on this forum challenge or dispute this simplistic view that I expressed, it will be taken positively. Ideally speaking, if car manufactures publish their component failure rates (aka ongoing reliability monitors) as the electronic component manufacturers do, lot of these assumptions could be validated. Assuming that the car manufacturer sourced their electronics from tier-1 suppliers, the reliability, even with high number of electronic components is not so bad after all. Is it too good to be true? Perhaps not, as the reliability of electronic components is getting better and better – read 10 FIT (10 fails in 1,000,000,000 hours !!!).
Key Assumptions:
1. All electronic components (including sensors) have similar failure rates (< 100 FIT).
2. Number of electronic components in the car assumed to be 40 to 50 (actual number unknown).
3. The electronic system design conforms to the auto industry standards. (but looking at initial niggles, I have some doubts here)
4. All electronic components in the system operate within device specifications. (A best quality part when used in a poorly designed system may not be reliable).
5. Any system malfunction indicators (lights on the dash) get serviced without much delay.
Are all my concerns removed?
1. Not fully. My analysis is based on a lot of assumptions and I could be way off.
2. How well the electronics tested in production?
3. Though electronic components by themselves are very reliable in isolation, a ‘small weak link’ (design flaw or untested manufacturing defect) in the complete system can compromise overall reliability.
4. How well the ASC and technicians equipped to debug / fix issues related to electronics?
5. What fail-safe mechanisms are provided (in case of safety system failures)?
6. Electronics are subjected to extreme conditions in automobiles (temperature, moisture, shocks, etc…), so actual reliability could be much worse than what my simple excel analysis says.
Big Question: Am I still keeping my W8 booking? Yes for now (as the value for money proposition, though not as high as I initially thought, is still there). |