Had one fail in my 914,there seems to be a common failure point around the top casing that fits to the main assembly,this design is the the same for early Golf,944,T 1 and T2 aircooled Audi and I would expect many other in "the family''.
The return spring mounts via a tab on the spring into a hole in the top assembly,repeated use causes the area to crack.
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The result is that the green plastic centre section loses tension and pops upward which in turn causes the metal wiper plate inside the switch to make a poor contact as it moves through its arc.
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The end result of this poor contact is complete or partial failure,the crack in the housing shown in picture 2 is from my early 944 switch this was enough to stop injector pulse due to insuffient power to my ECU.
I pulled a known bad switch from another VW I had and found no crack in the housing but the contacts inside were all gummed up as the grease had gone bad and the contact pins were oxidized,cleaned it and it worked in the 944 till the correct replacement arrived.

Yep....

Very common. My switch failed when it got really hot and then the housing cracked exactly as shown.

Part 2 of my rant ,you can tell I had nothing else to do today .
Two switches I pulled apart all had burnt centre contacts which is constant 12v,if the housing isn't cracked this appears to not happen as I found with the other VW switch.
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The real hassle is that until they fail completely which usually ends up with your starter grinding down your battery or nothing when you turn the key you just don't know ?.
Having read lots of posts on here and on the 944 forums about ignition/electrical and FI issues appear this little cheap nasty (design) part has a lot to answer for .

IMO more often the cause electrical problems that most know.

same what happened with my previous 75.

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So what is the fix?? I just bought a supposed "factory new OEM" switch off ebay today. Mine already has a push button starter installed as the PO was on his second switch. I am wondering if the broken switch I am still using (to turn the car on/off) is causing weird electric issues, mainly with the wiper blades working intermittently. Maybe I will install this new switch, but continue to use the push button starter. I don't really like the push button as it feels weird to stick the key in and turn it on but not go the last step.

Hi Noel,that switch is a standard failure ,I really wonder how long the aftermarket replacements last,I see a genuine Porsche on some vendors sites which is way more expensive...is it better ,time will tell.
Maybe someone on here has bought that genuine switch ?....comments please.

Is it true that a remote hot-start relay takes the pressure off the stock switch and helps prevent the failures shown above ?

Thankfully, it's the same switch on mid to late 90-s vw cars.

Yep, see the link in my signature.

Just looking at those switches you can tell there was a fair bit of heat involved in their demise.

Yes. Every electrical component which is switched by the ignition switch requires electrical current. The ignition switch like any switch/contact has some finite resistance.

There are a couple of ways switching on/off electrical components wears out a switch:

1) Capacitive charging: We've probably all seen some arc when plugging in something to an AC outlet. An electrical component (relay, ignition coil, light, fan) all have some capacitance. When plugged in or ignition switch switched on, a very high current may flow when first connected to the point where an arc happens. This is not good for a switch and can prematurely cause failure.

2) In operation, a switch can get very hot from current flow. Every switch has some resistance. Current flow and resistance results in power dissipation (PD=I^2 x R) which results in temperature rise. High current = hot switch. Lower current = less hot switch. Heat over time may prematurely age plastic and physical stresses on plastic can cause the plastic to crack.

3) Inductive kick; When electrical components are turned off, inductance in wiring and the component try to keep the current flowing and can generate a large voltage and arc upon turn-off. The higher the current the higher the inductive kick. Again, not good for longevity of a switch.



Not sure a hot-start relay can prevent the failure shown but it can help prolong the life of the switch. The ignition switch in many modern cars are nothing more than a push button switch with very little current flow. Other high current switches turn components on and off as well as the starter.

The 914 use of the ignition switch is crude by today's standards. Any extra relay's or SSRs that take away current from the ignition switch is a step in the right direction.

Think about the current loop of the bendix in a 914. Current flows from the battery to the front of the car to the ignition switch then back to the bendix to ground. That's a very long loop.

With a hot-start relay, the current loop for the bendix is from the battery to the starter through the hot-start relay on the starter. Very concise loop with heavy wires.

Thanks ! That is a terrific explanation. Can you elaborate on the use/need of a suppression diode on the hot start relay,,,

Tom had mentioned this in a threaf

Yep your starter relay fix is a good one,Mark out of 2 switches didn't really see any real heat,but mainly bad contact on the switch contact arm,funny got one from the 944 and stretched the 3 contact springs and it worked after previously being useless but its not a real fix for a sub $10 part.

One reply on here was wipers that didn't work anymore,thats the first thing that happened with mine then other stuff tipped over before total failure .

I mentioned same design but not same switch,mounting points are different from model to model ,depends how they fit into the back of the ignition barrel.
The VW group later cars in many cases ditched this system for a more robust unit.....wonder why???.
A quick look on Pelican comes up with following;
meistersatz $8.25 ,have one in my car ok so far,
CRP $9 ,know little of this brand?,
genuine Porsche $40.50 ?.
That's why I asked if anyone had used the genuine one,honest think its a crap design can't see it making too much difference .

Note that the genuine porsche one from PP does not include a 20% increase and 3-5 week ship from Germany. PP should really update the listing that they don't have the part and have to order it from Germany. I cancelled my order of that one for that reason.

Here is a recent thread discussing Porsche vs. aftermarket switches. http://914world.com/bbs2/index.php?showtopic=311314 Sounded like the expensive switch was the way to go.

Sorry my bad,too many people buying the $8 part lol,pretty rude how PP do that considering they are moving boxes of stuff from Porsche on a regular basis.
bbrock that discussion never really came to a final outcome on the genuine switch,some having issues with the cheap ones however.

Pretty sure they are all made in the same factory.
Brazil or Mexico
99 vw eurovan is the same, took me three switches to get a good one.

I believe all the vanagons used this switch as well.

The diode is sometimes referred to as a snubber since it prevents a large voltage from developing across a coil when the coil is turned off. The large voltage can damage transistors and cause switches to arc and shorten the switch life.

The diode snubs the inductive kick when the coil is turned off.

A coil is an inductor. An inductor stores energy in the form of current and resists changes in current. The voltage across an inductor is given by the following formula:

V = L x di/dt

where

L = coil inductance in Henrys
di = change in current in Amps
dt = change in time in Seconds

How large can the voltage across a coil get when turned off? Here's an example.

Suppose a switch opens up to turn a coil off like happens when starting the car and the starter is turned off.

Let:

Coil inductance L = 1H
Current I = 1Amp
Say the switch turns off in 1ms (0.001 sec); dt = 0.001 sec
Therefore the change in current: di = -1 Amp

Put these numbers in the inductance formula:

V = L x di/dt = 1H x -1A/0.001sec = -1000V

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This is the inductive kick everyone refers to. Without the diode, the coil will kick back and may cause switch contacts to arc thus shortening it life. If controlled by a transistor, the high voltage may damage the transistor.

Placing the diode across the coil will give the current a path back to the inductor. The resistance in the coil, wiring, and diode will cause the current to decay to zero in a relatively short time.


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As 3D printing has evolved I've wondered if someone would pick up this project and do it right, once and for all. It's a complicated little part, but I would be happy to pay a premium for a part that I knew was designed and built well and addresses these issues.

Seems like the biggest issue could be just the material choice. Perhaps that type of plastic isn't up to the job...

I have a switch off of a VW and it has a metal case. I know it's off of an air cooled, I think T3.
I'd have to dig it out of my stash, very similar, but I know it wouldn't work on a 914 as it has wire leads.

Just mentioning this as a metal case could be made to work.

Anyone with first hand experience on the German ones? $40 or whatever for a switch that won't leave you stranded at the worst possible time is cheap insurance.

I would see if you can get it from your local Porsche dealer. I don't ever get charged a shipping fee and stuff usually comes in quickly even when the have to order from Germany.

Yes! I'm not sure if it's the same for earlier cars but the one I got from a Porsche dealer was about 35 bux IIRC

No problems after 3 or so years, the cracked original required a lot of torque to get the starter to engage; it gave up pretty quickly at a gas station nearby. I used the opportunity to clean up the steering wheel lock, change the bearing, and some other things, while I was in there...

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Here you go

Porsche OEM only, the cheap knockoffs do not last. Sometimes you need to buy several just to get one that works.

Be sure to lube the assembly as it goes in the barrel with silicone oil or silicon grease, because it binds easily as it rotates and can contribute to the case breaking.

Yea have seen that metal switch Mark ,got to be better,however if you have a less than average electrical system wiring wise or a dying starter surely that would have some impact on a less than well made aftermarket unit....must do.

I did call the local dealership, but the guy on the other end seemed below par for working in parts as he asked me for my whole vin number after I gave him the digits for my 73. I didn't have the part number and not sure he quoted me correctly but said somewhere around $170.

Type 1 part if I remember right,if I'am wrong please correct me...interesting,you have to love that german name on the bag .
So I may be guessing but think maybe first of the 1500cc beetles up to the superbeetle ,will check that part number and see.

I use our local one pretty frequently for small parts. I also get a shop discount. If you figure out the correct part number, let me know and I'll get you a price. I'll only charge you what they charge me. I drive past on my way to work so I stop in often.

Yes 111 xxx xxx is a type one VW part number.

111-905-865 L

Type one 1974 to 1998, I assume they mean Mexican and Brazil beetles
T2 (bay van) 1974 to 1979
Vanagon 1980 to 1992 except models with door buzzer.

I don't know what the part numbers are, all I can say is that the part that came in that bag is now in my car, and works great...

Thanks for the info on the "Genuine Porsche" switch. I went through Pelican to get mine. Upon notification that the part came from Germany, I kept that order and ordered a cheap one to keep my car going.

Installed the cheap one last year...it's failing after about 8000 miles.

I'll be installing the Genuine Porsche, hoping for more longevity.

Does anyone know if the part number above will work in a 73? I thought the last character "L" had to be a "K" or something else (another thread talked about it I think)

According to Pelican site the K is for 70-74 and the L is for 75-76. I bought the Meistersatz brand from Pelican in April and it's already starting to fail. I too was surprised by Pelican after ordering a genuine Porsche to get an email stating it would be a 20% increase and 5-6 weeks. I cancelled the order because I needed the switch for WCR and bought the Meistersatz, but now I'm In the same boat getting ready for RRC. I'll rig up a bypass wire until I can install an OEM switch.

I wish Pelican would stock the damn switches. Seems like there is enough demand to justify.

Coming from aircooled beetles I am wondering how this part would fair:

https://www.wolfsburgwest.com/cart/DetailsL...m?ID=111905865K

WW is usually spot on with period correct parts and genuine german made items. More so than cip1 and some of the other beetle parts suppliers. It doesn't give any details on origin or manufacturer though. I may just get this to compare. If it passes all check tests we could start using this as a replacement.