Hi guys. Has anybody ever had their wipers start on their own, and can anybody give me some tips on where to start checking. My Mexico was parked quite happily for a few hours at a show today near Newcastle. Nice sunny day, warm but not hot (for northern England!) and the wipers just started running at high-speed for no reason. Nobody had been in the car and the door was still locked when I got back to it. They wouldn't switch off so I had to pull the fuse to stop them. Any thoughts?
They're controlled off the dash switch as well as the foot operated screen-wash pump. I put the fuse back in tonight and the wipers didn't self-operate so whatever was shorting out before isn't anymore. It's going to be one of those annoying little things I think.....
Ivan Ruiz has a pdf file covering schematics for Maseratis 1964-1968. <http://thecarnut.com/Manuals/Electrical_diagrams_1964_1968.pdf>. There are lots of variants shown, but based on your description and the Mexico manual, schema 31 on page 34 of the pdf is probably the right one for your car. There might be a couple of other possibilities: the washer pump switch, or the internal motor contacts that keep the motor running outside the park position so that the wipers park regardless of when the switch is turned off. Good luck - intermittent problems are the hardest to find.
Paul, While you sort it out make sure to remove the fuse when not using the car. The last thing you want is for the wipers to start by themselves in the middle of the night. Something else to consider is to move the wiper motor to a switched circuit. This way they would only work when the ignition is switched on. Ivan
Thanks for the tips and guides guys. This going to bring forward the investigations as to why the wipers wouldn't self-park. May be related but in the meantime, the fuse will certainly stay out. Cheers, and here it is before the wipers went nuts.... Image Unavailable, Please Login
It might not be the evil overlord himself who haunts your wipers. Maybe just a demon he sent by the name of Vitaloni. Be sure to wear a solid protective necklace woven of Bosch relays around your neck when you try to exorcise your wipers. And then some (the Biturbo elder) say that Bosch relays bear the seed of evil aswell... Your wipers are doomed. Keep out of the rain by all means! PS: Nice car. Mine has the same colour. Sorry for not being of any help and just cracking jokes.
Cheers, it was such a lovely day and the Mexico looked great in the sunshine parked up neatly behind the line of Blackpools finest. Image Unavailable, Please Login
Yes, TVR T350c. Lovely little coupe with a 350bhp 3.6litre Speed 6 engine. Like a 'lite' version of the Sagaris. How and he's another gratuitous picture of the Mexico in the sunshine Image Unavailable, Please Login
nice Mexico but what happened to the chrome around the headlights? Are you goin for this look....? Image Unavailable, Please Login
Hi Dirk / Paul... I noticed that as well, and was going to ask... Attached is a picture of my car, which is not the best picture, but you can see the chrome around my headlights... Mike Image Unavailable, Please Login
Hi Paul... Any luck on your wiper issue? I gave some more thought to this and wanted to check with the experts here, as I certainly am no vintage Maserati electrics expert! When I read about Paul's wiper issue, my first thought was grounding. I mentioned this as the wiper circuit would have to be complete somehow for the wiper motor to do its thing. I could see this happening if the wiper switch itself completes the circuit by grounding it. If that were the case and somehow the wiper motor was able to get to ground, the motor would turn. But my quick theory produces questions: 1. Does the wiper switch ground the circuit or provide the voltage to the motor? 2. Is the wiper circuit switched, or supposed to be switched, meaning the key has to be on, before the wiper motor can be run? 3. What about the different speeds of the wiper, how could this be done if the switch grounds the circuit? I am hoping someone can provide some input into this. I may be all screwed up on this. But under my scenario, I could see how the wipers could potentially come on by themselves! What have I got wrong and/or what am I missing? Mike
This is a look at how a typical Lucas wiper motor works. This example is for a single speed but the concept is the same. The wiper motor has 12 volts going to it. Maserati most likely put the wiper motor on an un-switched circuit, which I don't think is the best way to do it as it leaves you exposed in case of a failure. The dash switch grounds one of the brushes which makes the motor run. In addition there is a parking switch connected to that same brush. During most of the gear rotation the switch will be closed thereby also grounding the motor. If the dash switch is turned off (as in this image) the motor will continue to run (since the parking switch is grounding the brush) until the gear reaches the point where the parking switch opens and the circuit is broken. Although possible I doubt the dash switch is at fault. I would look closely at the parking switch. It may be something as simple as old grease drying up and not permitting the switch to fully open. Ivan Image Unavailable, Please Login
Hi Ivan.. Good information.. Sounds like I was partially in the ball park in that the switch grounds the circuit, and if the motor can get to ground by some other means, the motor could/would keep running. Agree that the culprit here is most likely the parking switch. If it can't get to it's 'off' position, the motor would keep running... Thanks... Mike
In the 64-68 PDF, schematic 8 shows three variants grounded through the switch, and they use either a three wire or six wire motor. Schematics 28,31,35,and 43 show systems with a five wire motor grounded locally through pin 1 of the motor connector. With that clue, Paul could start with the right schematic. I thought schematic 31 made sense because it's the only one that shows both a foot pump and a non-column switch.
Nothing sinister, The chrome was a little thin on the faces so just fancied trying a slightly different 'look' instead of the full chrome as original. If I decide to keep the Mexico I'll get them re-chromed over the next winter lay-up.
Thanks for the suggestions on the wipers. They should be wired negatively so they will run and run until they self-park but from my basic testing, that isn't the case so there is a gremlin in there somewhere. The self park works properly (I've dismantled it and tested it all) but the wipers wouldn't self-park in operation. Checking the serial number of the actual switch it doesn't match that on the wiring diagram so that may well be the problem. What is unclear and more than a little confusing is why they started on their own several hours after the car had been parked up and locked... Ghosts in the machine lol !
Hi Paul - just a thought. If your car is wired like schematic 31, then the washer pump switch has a feedback path (orange wire) for the self-park function through a set of contacts that are closed when the pump is not in use. It also has a set of contacts that turn on the motor when the switch is closed (I assume that's when you push a pedal or something). If that switch armature is flopping around loose, it could cause both problems - no self-park, and unexpected wiper operation.