My VW still hates me — flat batteries suck

Didn’t manage to start my car today again ;-(


The more I use this thing, the less I like it. I only get about a minute worth of cranking out of it. The battery claims 17Ah, but given that the charging circuit doesn’t really permit more than say 400mA of current… I can’t really be sure this thing was really full. Maybe the battery is a piece of crap as well.

When it didn’t even turn the starter any more, the test-button still indicated 75% full. But that only measures voltage… Internal resistance seems a bit on the high side.

If the starter pulls say 250A, I’d expect to get at least 2 minutes on starter action out of this thing…

I guess I’d haven been much better off buying a car-battery charger… It seems this thing is really only good for assisting a weak battery, not to fully replace it. Oh well…

The charge-regulator, if you want to call it that, is a 3.3 Ohm resistor! WTF. The reverse-polarity protection diode was a 1N4007. I’ve replaced it with a 1N5817. The max. reverse voltage is just 20V, but at least the voltage drop is much lower. Not that this helps to get the battery fuller quicker, now the resistor will get warmer.

But I had to do something!

Changing the diode was “something”. So I had to do it! Infallible logic, just like the arterycloggingsaturatedfat theory.

Currently I’m charging the starter-box and the car’s battery, maybe that will be enough to get the car going again. I can only hope that having removed the broken vacuum pump doesn’t somehow upset the car’s brain and keeps it from starting. The gasoline-pump seemed to be on (heard the noise), but it seemed there was absolutely no ignition going.

I have a very bad feeling that the car needs a visit at the garage. Last year I had the anti-locking break thingy replaces (hydraulic valves + stuff), cost me a fortune… and the damn warning lamp was on again recently.

I think after this car expires, I will not buy another one. Renting a car / taking a taxi once in a while is certainly cheaper than owning a car. Less hassle too.

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