Throttle Position Switch - 1973 Volkswagen Type 3

Good afternoon, Forum!

I have a Throttle Position Switch (VW P/N 311 906 111 E). Problem is, there is a missing "Cat Whisker" (the tiny wires that alternately contact the two vertical gold posts, depending upon acceleration/deceleration). Missing is the one that would ordinarily engage the wiper that touches (alternately) "Pin 9" and "Pin 20" on the main connector.

Question is; does anyone have a means that has worked to replace the missing "Cat Whisker"? I am fresh out of suitable materials to fashion one in the garage.

All Help Greatly Appreciated!!!

Hi Scott,

I am not sure what you mean by cat whisker. Can you show a picture?

Hi,
please post the Bosch - number of the switch.

I own a OPEL, but my TPS is the same as in some VW Type 3 - Bosch 0 280 120 019.

I append photos you can download, mark the defective part and repost.







Regards
Norbert

Sure - Photo attached





The Cat Whisker is the single gold wire extending from the silver/grey terminal to the gold post. There should be two cat whiskers - One for each gold post.

Thanks for your reply!

White arrow shows "Cat Whisker" wire in place Blue arrow points to where the missing wire should be.

Hi Scott,

if I found correct translation it is called following contact. However there is only one 3rd party spare part for throttle switches: the PCB board. However you can pull off the complete finger and try to fit one of another throttle switch where the 3 sliding contacts have the same angle as yours.

Sorry, there is no better help. I found one with the Bosch no. 0 280 120 024 on ebay DE. But being a new part, someone asks 179€ for it.

What you call a wire is a blade with a contact point on it.

Bosch # 0280 120 024

Thank you very much - Great help, actually. I shall fire up the fabrication shop and see what I can do here locally.

Thanks again!

Hi,
the part seems to have been modified before - compare with the photos I posted!

As a workaround you could solder a sheet out of a relais or just a solid copper-wire on the blade:



This will do the job until you get another TPS. The electrical current is very low, the wire just has to fit mechanically.

Regards
Norbert

Thanks - I put one together and it seems to be working fine. I received a new wiring harness for the fuel injection and have a question with regard to the TPS: The pin marked "12" at the TPS connector now terminates at "Pin 11" on the ECU. All others terminate where expected. Is this acceptable (and) is a 1973 Type 3 Volkswagen-specific schematic available? I find some, but with either "Pin 14" empty (older type) or one with "47" in the place where my "12" is.

Thanks!

Hi SCott,

you will often find 12, 14 or 47 on those TPS. Why? Depending on your car, it can be connected to pin 12 (usually just ground), pin 14 or external round pin 47. However it always has the same meaning: Supply of ground to TPS which is fed back by all the orther contacts of TPS to ECU.

Hi Scott,
a little bit surprised to hear from you again, one year has gone...

The marks '12' and '47' have the same meaning. They are also both stamped at the same pin of the TPS.
Connecting pin 12 to pin 11 inside the wiring is not the best (original) solution - but it is acceptable because the leads are connected inside the ECU.

Most of the diagnostic testers would not notice this as an error, because they bridge the pins, too.

Where did you buy the harness? It could be changed to the original layout - but I think you need not worry much about this aberration.

I could help you with a correct schematic if you would post a 'real' email-adress via PM.

Regards
Norbert

Thanks! Makes sense. A bit confusing when looking through all the Internet based documentation, especially when so many use (as you indicated) different pin numbers for the same purpose and different part versions (like the four-pin versus 5 pin TPS).

Thanks again!

Thanks Norbert - Real email is scott_mccrea@yahoo.com

The bridging of the pins makes sense and since that is the case, the cable indeed is quite correct.

The cable is from Jeff Bowlsby and it is of very high quality and execution. Jeff in fact sent a note as I was posting my question addressing this point exactly, as I am sure he anticipated my checking pin-by-pin the connections. Very good job making this cable.

Hi,
Jeff is THE specialist for the wiring harnesses in the USA and produces high quality. This will fit and work.

He is member here in the forum, too...

Regards
Norbert

--- will send the schematic later, no time left at this time -