His windshield wipers seem to have no ‘off’ switch

Dear Car Talk:

I have a 2006 Chrysler Town & Country with an interesting problem. A few weeks ago, I was driving in the rain with my wipers on. When I parked and turned off the car, the wipers kept going. At first I thought I had the key in accessory mode, but the ignition was off. I then turned the car back on and off again; the wipers still kept going. Then I took the key out of the ignition. The wipers kept going. I had to take out the windshield wiper fuse in order to get them to stop. When I put the fuse back in, they start right up again, even with the car off and the key in my hand. So now I can drive the car only if it is not raining, or put the fuse back in if I have to drive in the rain. The wipers will go from normal to fast if I change the setting, but will not operate in the intermittent mode. Any help with this one is appreciated. Thanks. – Steve

RAY: Well, look on the bright side, Steve: Now you have a perfect excuse to say "no" when anyone asks to borrow your car.

I have a couple of ideas for you. One is to find the windshield-wiper relay. You’ll find that in the fuse box; it’s even labeled! There should be at least one other relay in there that looks identical. Try swapping those two relays.

If your relay is stuck in the “on” position, that could explain why power is continually going to your wiper motor, even after you remove the key and leave for two weeks to Honolulu.

When swapping the relays doesn’t make a difference, my second guess would be the wiper motor. That’s also pretty easy to test.

The windshield-wiper motor is right up against the firewall. With the wipers on, you’ll be able to hear and identify it pretty easily. It actually just plugs right into a socket on the firewall.

Come to think of it, maybe you can just buy a Clapper, plug it into that outlet, and control the wipers that way.

Actually, what you’ll want to do is go to a local automotive recycling center (aka junkyard), and buy a used windshield-wiper motor for $20 or $30. But don’t install it. Just plug it in, and test the wiper switch to see if the new motor stops when you turn off the wiper switch. If you can turn off the new motor with the switch, then you know the problem is your old motor, and you can replace it.

If it’s not the relay or the motor, then you’re getting into poltergeist territory, Steve. That could require an actual mechanic, a wiring diagram, a voltmeter and maybe a couple of hemlock roots and an eye of newt. So I’ll hope one of my two ideas fixes it.

Alignment check can confirm if there is a control arm mix-up

Dear Car Talk:

I recently replaced the inner and outer tie rod ends, ball joints, axles, CV joints, front tension strut bushings, and control arms (with bushings and ball joints) on both sides of my 1993 Ford Taurus GL. I also did a rough alignment afterward. The shock/strut assemblies were done earlier this year. I've since had the nagging feeling that I may have mixed up the left and right control arms before I installed them. I don't think they're interchangeable, because they have different part numbers (K8425 and K8427). How can I figure out now whether I switched them by mistake? – Laura

RAY: This reminds me of the old adage about the criminal always returning to the scene of the crime, Laura. Like said criminal, I'd advise you not to go back there.

Actually, if you’re lucky, there’s still a decal on one or both of the control arms. Or maybe there’s a part number stamped into the metal. You might be able to get under there and find a part number and confirm it that way.

But it’s not easy to put them in on the wrong sides, Laura. I suppose if you really force it, you might be able to do it, but then the car would be almost impossible to drive. So if the car is driving more or less normally (or whatever counts as normal on a 1993 Taurus), you probably got it right.

If you want to be sure, take the car to an alignment shop. You definitely need an alignment anyway. A rough alignment – where you look at the wheels and say, “Hmm, they’re both pointing more or less in the same direction” – isn’t worth squat.

If the alignment shop is able to align the car, then you can rest easy, because there’s no way they’ll be able to align it if the control arms are on the wrong sides.

The only downside, I guess, is that you may expose yourself to potential ridicule. If you did somehow reverse everything, the guys at the shop may laugh at you. But at that point, you can either confess and take your lumps, or you can tell them you had it done at my shop, mumble something about “those morons,” and throw us under the bus. Good luck, Laura.

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