The Lotus Grand Tourers

Pete Boole wrote:It's probably just a "555" timer circuit triggering the relay. I can't see it affecting the self-parking function though.

Pete

Correct, the delay module plays no part in parking and, in fact, can be unplugged leaving just the slow and fast continuous wipe, IIRC.

That looks like must be an early version of the A revision module, The one I got from Big Jim has 4 or 5 555s in it, and the Pektron module (revision C) doesn't have any - relying on a set of RLC circuits instead.

Bash,
Which Lucas wiper motor is used in the Excel? I wrote-up something that applies to the Lucas 14W, 15W & 16W wiper motors, including parking; but it got long and I don't want to dump it on everyone here just to find out that it does't apply.

*~*~*~*~*
In your photos of the open Wiper Delay box, there are a number of blue-wrapped 'tin cans'. They're electrolytic capacitors, they dry out with age, and stop working. A lot of period electronics, from your favorite old audio amplifier to the Wiper Delay box are now old enough to be quiting due to bad electrolytic capcitors.

Replacing the capacitors (re-capping it), will often restore the device to normal function. And it's not difficult. The capacitor's rating and polarity are marked on it's side. Just solder in new capacitors of the same rating, making certain to get the polarity right. Or take it to any electronics repair shop that might also work on appliances or audio equipment, and pay them to do it.

I'm not saying that is your problem. But if I opened up an old, 'iffy' component and saw all those electrolytic capacitors, eliminating one possible cause by replacing them would be my first step. Even if they're all still good, they're on the brink of failure just due to age, so it's not really wasted effort. (To any owner of a Turbo Esprit with Bosch fuel injection.... the Bosch components are full of electrolytic capacitors.)

I'm with you... I relate to cranks, gears and cams, and I don't like electrons. But I've suffered through some professionally forced exposure to electrons, and a wee bit of it sunk in thru my thick skull.

Good luck,
Tim Engel

Aah ha, summat I understand thanks Tim, little blue tins gets my vote, as for '555' stuff....... its just stuff to me. Electronics passed me by at the stage where I asked how electricity passes thro a wire. I will have a look at the motor to ID it when I next get the time but Im determined to get to the bottom of this, hopefully without having to find whats black, smokes and dangles from the ceiling with spikey hair, ie, an electrician.

Bash

When I take the motor off I will be having a look for this ....
https://majcd213.blogspot.com/2014/06/w ... rking.html

Bash

That switch failed on my Excel. Normal service was resumed after replacement.

Pete

Bash,
You can replace the little park switch in the blink of an eye. It's removing the wiper motor from the car and replacing it that will take all the time and effort. Good luck with that part.

I have two Eclats, no Exel. For the Elite-Eclat, I once read that the factory suspended the wiper motor in mid air, then built the rest of the car around it. I presume the same holds true for the Excel.

Have fun with that,
Tim Engel

Excels are piss easy, unscrew the wood off the dash, two screws to pull the panel with the guages out which are all on a multiplug, unscrewing the speedo cable at the same time and its straight in front of you on the bulkhead. The bit of the Excel that they dangled from the ceiling and built the car around is the pedal box, done one, still traumatised.

Bash

Easy is a relative term.

viewtopic.php?f=27&t=10489&hilit=Wiper+motor

Ahh well, thats what happens when your fingers are like sausage rolls.
( I'll get me coat and tin hat )

Bash

Well the temporary cure of removing the fuse has been superceded by a spot of damp weather, so Ive had another go. I replaced the park switch, which can be done without taking the motor out, (if anyones interested Ive photographed what to do) so was easy, still the same. Tried a direct earth to the battery, still the same. Checked and cleaned all the relay connections ( I replaced most of them recently), ditto. It still does not do it if the delay module is disconnected and the wiper still works like this on slow and fast speed, but, and I still cant figure this out, even with a new park switch they still dont automatically park with the module disconnected. So Im going to try a replacement delay module next.

Bash

Case solved, it was the wiper delay control module and I can confirm that the park function is controlled by the box. A replacement box means that the issue has gone.

Bash

bash wrote:Case solved, it was the wiper delay control module and I can confirm that the park function is controlled by the box. A replacement box means that the issue has gone.

Bash

Nice one.

Just wondering... when the delay is working, the screens by default tend to be only semi-wet /almost dry so the blades would drag against the motor. Could there be any current-surge feedback to the delay module, or does it work in isolation of the main current flow to the motor (like a relay)?

Sorry its question beyond my pay grade really but the delay wipe function was getting less and less reliable throughout my fiddling until it was only working when it felt like it. Mike Taylor confirmed my suspicions about the park function but a replacement unit ( one of the later units) stopped any issues at all. I thought that because I was getting two swipes of the wiper on startup that it was the washer circuit, but I was wrong..... again.

Bash

Glad you've got to the bottom of this one Bash and good that you've documented it for the rest of us. Interesting that the delay unit affects the parking function as well as the mechanical switch on the motor.

Pete