My VW hates me — or why rain sucks

In the beginning there was a light… a reading light… once turned on… it stayed lit. A couple of batteries had to die because of that. I’ve think I blogged about the buzzer-fix before.

In later years I killed a couple of batteries during winter time, as I often forgot to unplug the heating element for the driver’s seat.

Some time later another battery died, but the heating element was long gone and the reading light had a buzzer. What was is this time? By applying the ‘Sherlock Holmes Principle’ I quickly found out that it was the friggin’ radio. After replacing it with one I scored on ebay, all was good again.

So as you can see, my old VW has a long history of killing its starter battery.

And it continues !

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After a couple of days of heavy rain I wanted to use the car, but guess what… the battery was dead again. Fed up with that I bought a jump-start box, essentially a battery with heavy duty wire and some clips. It was able to crank the motor a couple of times, but it didn’t start… ARGH. Maybe it wasn’t fully charged, will try again tomorrow.

The internal build-quality of that starter-box is partially questionable. The spade-connector wire-terminals are of the locking-type, so they can’t vibrate off. Very good. On the other side we have quite a bad cable management, especially in the hose compartment of the compressor. If you aren’t careful, you can rip them out while trying to get the hose out. I also noticed that the nuts on the high-current switch weren’t tight enough for my liking. AND I found a loose nut floating around in the box. That’s a big no-no. Never heard of loctite? The power supply that came with the box is also a piece of crap. Should deliver 12V 500mA. I measured above 20V without load. Testing it with my dummy load revealed that I need to pull about 650mA (wore than what it is rated for) to get the output voltage down to 12V. I cracked it open and got rid of it. It was replaced with a 15V switch-mode one.

In the process of attempting to start the car with the box, I also noticed a strange noise in the trunk. To my dismay I discovered that the vacuum pump for the door locks was constantly clicking. It was soaked with water, quite warm and smelled awful. I think I should be happy it didn’t catch fire.

First I thought I should try to fix it, but the motor was shot as well. One of the bearings was gone. And I couldn’t find any useable information about the signaling needed to make this thing go. There’s quite a lot of electronics in there for a simple pump. You’d expect a voltage regulator, relays, transistors and so on, but there was also a mysterious chip with a resonator on there. Might be a micro…

I’ll have to get a replacement at some point, but I’ll have to get the car itself going first. I can live without automatic door locks for a while.

Enjoy the images.

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