The 99 relay comes is several sizes with different part numbers. "99" is clearly marked on top so they are easy to identify. They all function the same. All versions I've found are based on the ST Microelectronics IC number DD920402.

They can be hard to find because they are plug and play in some Volvo and BMW cars.

If you solder it might be a good idea to replace the few electrolytics on the board.

Here is picture of the factory W123 wiper relay showing the pin out for making an adapter.

Found this listing on a VW Bus forum. Afew more models it was used in.



357 955 531 (original VW 99 relay)
or 1HM 955 531A or B.
The Bosch # is 0-986-335-058.
The number stamped onto the end is "99".

357 955 531A, 1HM 955531, and 1HM 955531C are the NON-programmable intermittent wiper relays.

Check Ebay should be $20-30 or find them in your friendly neighborhood boneyard.

1990 Volkswagen Corrado
1991 Volkswagen Corrado
1992 Volkswagen Corrado SLC V6
1993 Volkswagen Corrado SLC V6
1994 Volkswagen Corrado SLC V6
1995 Volkswagen Golf Cabrio III ABA
1996 Volkswagen Golf Cabrio III ABA
1997 Volkswagen Golf Cabrio III ABA
1993 Volkswagen Golf III GL 4 CYL
1994 Volkswagen Golf III GL 4 CYL
1995 Volkswagen Golf III GL 4 CYL
1996 Volkswagen Golf III GL 4 CYL
1993 Volkswagen Golf III GTI 4 CYL
1994 Volkswagen Golf III GTI 4 CYL
1995 Volkswagen Golf III GTI 4 CYL
1996 Volkswagen Golf III GTI 4 CYL
1993 Volkswagen Jetta III GL 4 CYL
1994 Volkswagen Jetta III GL 4 CYL
1995 Volkswagen Jetta III GL 4 CYL
1996 Volkswagen Jetta III GL 4 CYL
1993 Volkswagen Jetta III GLS 4 CYL
1994 Volkswagen Jetta III GLS 4 CYL
1995 Volkswagen Jetta III GLS 4 CYL
1996 Volkswagen Jetta III GLS 4 CYL
1990 Volkswagen Passat 16V
1991 Volkswagen Passat 16V
1992 Volkswagen Passat 16V
1993 Volkswagen Passat 16V
1995 Volkswagen Passat GL 4 CYL
1996 Volkswagen Passat GL 4 CYL
1997 Volkswagen Passat GL 4 CYL
1992 Volkswagen Passat V6 AAA
1993 Volkswagen Passat V6 AAA
1994 Volkswagen Passat V6 AAA
1995 Volkswagen Passat V6 AAA
1996 Volkswagen Passat V6 AAA
1997 Volkswagen Passat V6 AAA




I found this on another car site in the UK (Lotus)
vw relay part number 357 955 531 (This has now been superseded with 3BO 955 531


If this is a superseded number I don`t know for sure, could be a UK or lotus thing.

Any word on similar vintage Audis?

Sixto
83 300SD

Just noticed that the 99 relay that I picked up doesn't have the extra wipes when using the washer fluid spray. The original relay would keep the motor activated to give a few extra wipes after letting off of the WW fluid.
Not sure if all versions of the 99 are like this or I should be looking for another.

EDIT: I found that if I held the washer button a little longer than I normally do, then I got the extra wipes.

Yeah, I like the 3 wipes 'mist' feature in the '83 300SD. I mean when I bump the stalk too quickly to squirt washer fluid.

Sixto
83 300SD

All my 99 relays include the wipes after pushing the washer button - same as the originals. I'm not sure why yours doesn't. It may be defective as the cars equipped with these are 20 years old now. Capacitor / solder joint failure is possible.

I haven't found one in an Audi and I looked in 20+ cars.

FYI: I have read that the number 198 relay is the same as a 99 but I can't verify that. I can also tell you the number 197 relay is a standard delay wiper relay so if you look under the dash and see a 197 move along - the car won't have a 99 or a 198.

There may be other good numbers too. If in doubt open the cover and look for the IC number DD920402. The 197 board has a relay and some circuitry but doesn't have an IC.

Does anyone have a schematic of this relay in it's "native soil"? I'd like to understand how it can be wired for a non-Mercedes application.

Isn't that answered in the first post?

Sixto
83 300SD

No. Simply labeling the pinouts doesn't show me how this is wired into a circuit.

The circuit is the same sequence of operation for either the 123 or 124. I got this from the 124 ETM. I would imagine that the 1st gen 126 shares the 123 circuit with the independent relay, and the 2nd gen 126 the 124 circuit with the N10.

If you have a 123 or 124 ETM grab it and follow along it will be much easier to follow with a diagram in front of you.

15 is switched live, hot whenever the key is in position I or II.
31 is ground
86 is hot when the washer pump motor is triggered from the combination switch (triggers the wipe while washing feature)
J is hot when the combination switch is in the I position (intermittent position- enables the intermittent feature)
S loops back through the combination switch, when it is is in either I or 0, it provides a path to the low speed terminal of the motor, and connects to the common terminal of the internal SPDT relay. This provides a path for the internal relay to either connect the motor to the park/wipe switch within the wiper motor, or to constant hot, but only when the combination switch is either in I or 0.
31b is the motor output (internal relay connects between S and 31b when de-energized - allows the wiper to park between sweeps, and between 15 and 31b when energized - pulses the motor on intermittent time basis).

Here is the power path under normal operation (position II of the combination switch) this makes it easier to understand what happens normally.
Power goes from the constant hot through the combination switch to the "low" speed winding on the motor. If you were to put the switch in position III then the power would go to the "high" speed winding. These are connected inside the motor in a "V" configuration, the low at the top left of the V, the high at the top right of the V, and ground at the bottom of the V.
The wiper motor also has a park/run switch, which is SPDT. If the wipers are out of the parked position, the common terminal has switched 12 Vdc, and in the parked position, the common terminal is grounded. The common terminal of the park/run switch is brought to the 31b terminal on the relay.

So when you turn the combination switch to 0, and the wipers are not in parked position, the power flow is interrupted from the normal path (through the contact that closes power directly to the motor from the combination switch contact) to the alternate parking path.
This path is:
Switched hot to the "not parked" position of the park contact. The motor is not in the "parked" position, so power flows out the common terminal of the park switch to 31b of the wiper relay. This is the normally closed contact of the internal relay in the intermittent controller. The voltage goes out the common contact of the intermittent controller to the combination switch. Then it passes through the second contact in the combination switch that is closed either in I or 0 position. From this switch it is internally jumpered to the hot side of the low speed winding.
This provides voltage to the low speed winding until the wipers move into the parked position. Once the wipers reach the parked position, the park contact moves to the "parked" position, which applies ground to this circuit. This not only removes the voltage to the motor to make it stop moving, but it also grounds both ends of the motor windings, which acts as a dynamic brake to make the motor freeze at that position, instead of drifting on. If it did not do this the wipers may float back up due to inertia, to the point where the park/run switch flips back to the hot side, and the wipers would run again.
Ok so that is the normal operation. The intermittent operation is just like "parking" except it does it over and over again on a timed basis.

When you go to position I, this energizes terminal J, which energizes the relay momentarily (for about 2 seconds), the relay de-energizes, the timer runs the time delay, and then the relay is energized for 2 seconds and the cycle repeats as long as you are in I on the combination switch.
While the relay is energized, it applies voltage to the line coming from the park/run contact back through the combination switch second contact to the low speed winding. In effect what happens is the motor runs, parks, runs, parks repeatedly every time the relay pulses.

When you wash in the 0 or I position, terminal 86 goes live, which energizes the relay long enough to get 3 wipes then it either shuts off automatically (0 positon) or goes back to intermittent operation (I position). If you wash in II or III it just pumps while constantly wiping since J is not energized.

What VW did to their relay is add internal logic that detected how long J was energized to develop the time basis between wipes, instead of just having a fixed delay like MB did.

Thanks. That should do it.

Yep, my 92 has the 19 relay. No Pick-n-pull yards around here so had to resort to Ebay. Got a 99 relay $11 shipped local US. Plugged it in my Jetta and it works as advertised. Not sure if I will get a 99 for my W123.

Most sources of 99 relays seems to come from Europe
357955531 | eBay

FYI, if you ever find one of the KAE 99 relays they are "programmed" in a different way: instead of turning the delay on and off, you tap the windshield washer.

My Mk2 Jettas (85, 91, 92) and C3 Audi 5000 had fixed interval 19 relays. I upgraded all of them to the 99 relay. Oddly, by 98 / 99 the Mk3 Jettas had gone back to the 19 fixed delay relay. B3 Passats always had them, however those cars are just about all gone now :(

Eventually I want to put one of the 99 relays into my SDL. My plan was to simply disconnect the wiper motor wires from the multifunction relay and stick the VW relay in the bottom of the fuse box.

Here's the VW owner's manual supliment from 1994 showing how the system operates: https://youtu.be/zCHp2Qg_ngI?t=6m46s

PS: If you want another VW relay upgrade for your MB, why not add tap to pass turn signals? http://www.peachparts.com/shopforum/tech-help/275418-how-retrofitting-tap-pass-turn-signals-your-w123-w124-w126.html

-J