This is the story of a little black relay. It started life at the Doduco plant in Germany, then immigrated via a blister pack to Neuspeed in the USA. Around 1991, I purchased it and plugged it into a 1990 VW Corrado. When I sold the car, I pulled the relay. Then it found it's way into a 1999 Porsche Boxster. That is, until I drove a Lotus Elise at Deal's Gap (courtesy Mike Silberman of Lotus of Durham
), and knew I had to sell the Boxster. But not that relay. It came out and went on a shelf pining for the Elise. I'm pleased to announce that this 15 year old relay has found a new home, in my 2006 Elise delivered earlier this week.
This relay is a marvel of Teutonic engineering. Simple, transparent, intuitive. Daily drivers will wonder what they ever did without it. Being smaller than the stock relay, it may actually improve your 0-60 times. Curmudgeons will rue the day, as this is too much luxury for them to handle.
What does it do?
It does two desirable things for the Elise wiper system. The major one is the programmable intermittent time function. The minor one is it changes the number of wipes during a spritz to 3 instead of 5.
Instead of wiring up a potentiometer and repeatedly twiddling with a knob like you normally have to do with most cars, you can set a comfortable interval on the first try. No hacking up the interior, or splicing wires, or changing stalks. Just replace one relay.
Here's how it works... envision that it's misting on the windshield due to the weather in the canyons.
1. Flip the wiper stalk to the intermittent position to clear the windshield with one pass, then flip it back off.
2. While off the relay begins counting. In German...
3. When the mist on the windshield needs another wipe, flip the stalk back to the intermittent position.
4. The relay will now wipe the windshield based on the time interval that you set. The relay can "count" between 2-45 secs. The limits may vary by manufacturer.
In other words, push up on the wiper stalk to the intermittent detent to have it wipe once, push down to off and wait until you need to wipe again, then push back up to the intermittent detent and leave it there. Ta-da!
If you've not used the intermittent since starting the car, the intermittent default time is about 6 seconds, IIRC.
This hack may be familar to the VW owners out there or Europeans. It's very popular.
VW carries the relay: either 357 955 531 or 1HM 955 531B
Some VW aftermarket suppliers carry it as well. Cost ranges from $10-50 depending where you find it. Here's one for about $29 + S/H: World Impex Relay
Replacing the relay requires some dexterity. More so for the Elise.
First find the relay. It's mounted beside the hazard light relay. Turn on your hazard light and gently feel around for the relay block, located above and to the right of the OBDII connection port. There are two relays there, one above the other. You'll feel both of them pulsing due to their proximity. Turn off your hazard light. The lower relay is the wiper relay. To remove it, I found it was far easier if I opened the passenger door, and sat in the drivers seat with my feet out of the car's passenger side. Pull the relay towards the drivers door to free it. Pay some attention to how the relay was rotated when you pull it out. You can't insert the new one the wrong way, but it will save time if you have the correct orientation. Look at the pins, and replace with the new relay.
And remember before attempting any project, be sure you possess the ability to perform the task correctly. I'm not responsible for running part changes, twisted backs, damage you may cause to your car, etc.
P.S. Thanks to Stan for putting up with my repeated PM's for electrical schematics. It wouldn't have happened without his info.