My guess is low current capacity switches molded in cheap thermoplastic material, that was not sufficiently fire retardant. These things keep happening mostly in aftermarket power window switches or AC solenoid switch etc. Also could be accessory switch and wiring underspecified or not sufficiently QC'ed. But the material properties appear to be prime suspect.
When I worked for an electronics hardware company, we used to choose ABS plastic with good fire retarding properties for enclosures for the export market - but the supplier - Your dear GE plastics - charged so much that in the price conscious Indian market, we were forced to use _any_ material that met the price point, fire retardant properties be dammed. - such are the pressures of cost in a dog-eat-dog market, coupled with regulator apathy.
I have seen on other local forum a
well documented 3000+ km journey in a Nano - mostly a publicity stunt, plus an attempt at finding suitability to Indian conditions done, and apart from a freak accident, nothing was found to be amiss.
(Disclaimer: I am a mod there, but I do not benefit in any way from the site, so feel free!
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