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2013-09-16
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General Motors Quality Failure

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So I’ve never really been a fan of American made cars, the companies have been building an inferior product to Japanese and European models for decades now. But presently, I’m saddled with a 2008 Chevrolet Equinox. And at exactly 100,000 miles, it’s started having all sorts of problems (stuck sunroof, broken power locks, P0455 that won’t vanish with new parts, etc. etc.)

Its the most recent problem that really sealed the deal on absolute crap quality from Detroit. While driving, the radio system just started shutting things down … speakers and then the whole radio, followed by turn signals. And then after turning off the vehicle, it wouldn’t start. Went through the usual routine of attempting to jump the vehicle with a portable jump battery followed by another vehicle to no avail. Huh, maybe it wasn’t a dead battery but a bad alternator? A digital multimeter confirmed the Equinox’s battery was fine and held plenty of charge.

Soooo, completely disconnecting the battery (performing an ECM reset) managed to make the vehicle start just fine (without a jump). Weird? Well, the manual (page 3-17) talks about:

EPM [Electric Power Management] works to prevent excessive discharge of the battery. It does this by balancing the generator’s output and the vehicle’s electrical needs. It can increase engine idle speed to generate more power, whenever needed. It can temporarily reduce power demands of some accessories.

WTF? The engine computer will decide to turn accessories like my radio off? Why isn’t the default alternator producing enough power for the factory installed configuration? While that explains the accessories powering off before it all went to hell, that doesn’t explain the inability to start. Maybe it’s due to General Motor’s Factory Service Bulletin #02-06-03-008D: “Low Voltage Display, Lights Dim at Stop Lights, Battery Discharged, NO START, Slow Cranking, Dim Lights at Idle, Low Generator Output.” Reading further into the service bulletin includes this text:

Any vehicle may have a low voltage display (if equipped with gauges), lights that dim at stop lights, slow cranking, no start, low generator output at idle or dim lights at idle when electrical loads are heavy at idle or under slow driving conditions. These characteristics may be more noticeable with customer added electrical accessories, or with a discharged battery. THESE ARE NORMAL OPERATING CHARACTERISTICS OF A VEHICLE ELECTRICAL SYSTEM AND NO REPAIRS SHOULD BE ATTEMPTED UNLESS A PROVEN FAULT HAS BEEN DIAGNOSED.

Note that all the previous emphasis was mine. Seriously? A “no start” condition is considered “normal operating characteristics” for a completely stock vehicle? It’s pretty bad when your quality control is so bad that a failure to operate is considered normal.

So why did the vehicle start working after the ECM reset? Most people may not realize it but voltage regulation for modern alternators doesn’t come from dedicated electronics anymore. The signals are processed by the ECM which in turn provides a signal back to the alternator to electrical field properties to affect produced amperage. This allows the ECM to manage the voltages and current based on all known sensors (load, RPM, etc.) In theory, it could allow the alternator to run the minimum field necessary and reduce load on the engine for reduced resistance but what it really means is buggy software can result in not enough charging. Oooorrrr, it could result in the ECU getting faulty readings at startup and determining there isn’t charge and not turning over the engine.

Regardless of whether there is an explanation, it strikes me as poor American engineering to either put in an alternator incapable of meeting factory load demands at idle or that the ECU is programmed so poorly as to require a complete reset in order for basic operations like voltage regulation to take place. And then for the manufacturer to simply write it off as “normal” and offer no repair (while probably charging customers) is all the reason to abandon Made In The USA vehicles.


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