My 340 already had an intermittent wiper but the interval was fixed. I thought, autumn is coming, and rain. I started planning to make my own timer relay, but nothing ever came of that. Then I bumped into VW programmable wiper relays (VAG 357 955 531 / marked "99" on the relay) on eBay and bought one, since the price seemed reasonable, got mine for a bit over 20 euros including shipping. I looked at the 340 wiring diagrams and the connections seemed to be exactly what were needed. So one rainy lunch hour I plopped out the instrument panel, located the wiper relay (easy, it's the only one with six pins), removed the original relay from its socket, replaced it with this VW "99" relay, put the instrument panel back in, and now I have a programmable timer for the intermittent wiper. The location of the relay behind the instrument panel: it's the one on the top.
The VW relay installed in the socket, with type code visible.

After all this I found out that several others also had the same idea, for example http://volvospeed.com/vs_forum/index.ph ... vw-or-ipd/

Very interesting. The fixed speed isn't that useful really, as it's always either too fast or too slow!

Copied from your linked page:

USING YOUR NEW RELAY:
The stock intermittent speed is not adjustable. The new relay is completely adjustable, with a 2-22 second delay iirc. You program it as follows:
1) Push up wiper stalk to intermittent position
2) Return to "off" position
3) Wait desired interval then push back to intermittent. Whatever time delay you set it with, it will remember that speed until you rest it again.

Tom

Out of interest/ignorance, how does the timer work then, how do you adjust it, or does it have a different speed setting to the Volvo one, i'm confused

I think it comes with a little dial you can adjust the speed with

Tom quoted the instructions. It needs no extra buttons or dials, you just use the wiper stalk to program it. Neat. Of course you need the car to have the fixed-interval intermittent wiper already installed, or the installation will get a bit trickier...

It was an option on early 343s once:


That twiddly knob is the variable intermittant wipe ...

Tom

I never knew these existed! Thanks Nomead, I'll be getting myself a couple from scrappies

Fitted mine this afternoon, and had a journey with it since in the fine misty UK rain. That has to be one of the best free mods I've done, relay was part of 2 good armfuls of scrappy bounty which my mate wanted

So to clear this up you also need an aditional adjusting dial/knob to make this work yes? I can't fit it to my poverty spec DL?

magnumpi wrote:So to clear this up you also need an aditional adjusting dial/knob to make this work yes? I can't fit it to my poverty spec DL?

no; with the original handle you "program" the relay itself, the timer is built in to the relay. the only thing you need to do is swap out the relay, that's it.

Yup, it really is just a case of swapping the relay. Super simple pocketmoney mod.

Cool tip then may just give this a go myself.

You need to have the fixed-interval intermittent wiper already fitted, otherwise it will be a lot more work. My -89 DL-spec has it, though, so yours might, too.

Yeah mine has got the fixed intermitent wipe so should be good to go.

by fixed intermitant, im guessing you mean, that the wiper system has to have the intermitten function and not just an on off?

cause i have intermitten on mine, lol, but ive never heard the term fixed, unless by fixed it means fixed in the sense that it will do one sweep in so many seconds?