Hella blinker/emergency light relais TBB26

[fourteenten]

Circled No 40 is the brake warning light switch and goes directly to light in the combo gauge, possibly via a relay but I can't find that relay anywhere in the wiring diagram. Or are the non-circled numbers the numbers on a relay? The keadlight relay 50 is pictured though. Or is the emergency switch relay combined with the switch in thr diagram?
BTW, brake light switch is USA only so in theory my car should not have one...

I think I start to confuse myself

Regards,
Cees

[McOtto]

Agree, US spec may be different and it is appropriate to recognize that, but my parking brake light blinks when the handbrake is engaged because the switch on the handbrake grounds the circuit from the flasher relay. I think I am correct in stating all of the blinking functions (directional, handbrake, emergency flasher) are all driven by the same flasher relay. In my US Spec case, a Hella TBB3 which in my experience is the only relay that works as Dr. Porsche intended.

If you have the original Hella that was in your car, you might try pulling the cover and cleaning the contacts with Deoxit. That worked for me.

[fourteenten]

That's a good idea, will try that. Been searching the net for the old style Hella relays, did not find a TBB44 but one TBB3, and we know that TBB26 was used as well. Several other numbers like 23, 38, 47, 52, 53 and 56 for other cars then Porsche.

Regards,
Cees

[911MRP]

This is a spare Hella TBB44 4DB003425 which is same as the part that’s fitted to my 73RS which has original system that works to spec that now has never been touched in over three decades in my ownership. I can’t be sure the one in situ is original as only had car since the early nineties.

While I’ve checked behind the dash on my car and can read the markings, it’s hard to get a photo in situ and don’t want to unplug and disturb what’s there but can confirm it’s Hella TBB44 4DB003425 and to Gitesh’s point is 2(4) x 21w + 0 .. 5w12V
IMG_6510.jpg

I’m not sure if the evolution of parts but this might equate to Porsche part number 914.618.303.11 as shown in paper copy of my 72/3 spare parts manual 9/72 applicable to my 73 RS era :
IMG_6514.jpg
Whereas TBB3 is equivalent 914.618.303.10 which was the number in the prior year’ Porsche factory maroon spare parts manual model 73. I have some evidence of that Hella to Porsche part number cross correlation. This sticker is on this relay:
IMG_6391.jpg
IMG_6390.jpg

Cees with your car being Italian supplied without hazard perhaps it’s not stock or maybe the one you show was original equipment and the one on my car and this spare is a replacement.

There is a what looks like 048 stamped in ink on one side of the spare not sure what this code means as I thought Hella had alphanumeric date code system with letter at the last position It is not very clear be an O not zero but other Hellas I have have three digit numeric. Can’t see the ink stamp on the relay that’s been long in situ.
Steve

[fourteenten]

Thanks Steve for the comfirmation. Last Friday I checked out a 1974 build 911S US Targa and that one had a TBB 26 relay in it. Still not conclusive that ROW cars got the TBB 26 as well during MY73.

Regards,
Cees

[911MRP]

This is a used TBB44 and a new old stock one
IMG_6615.jpg
IMG_6616.jpg

The NOS example has no evidence of the four spades ever being inserted in a holder, Hella have changed the graphics in the top but the numbers are identical ti the one fitted to my RS even the suffix — that might be my original but is certainly untouched by me for over three decades. This base has changed in markings ans material but the terminal are the same.

The relay is reasonably accessible however I assume the cover could be swapped if the more modern graphics deemed not ok by purist but the markings not easily readable in situ

Steve

[fourteenten]

Thanks for sharing Steve, interesting to see that Hella produced another version, probably same functionality (has is to do with DOT stamped approval?) and more chance to find a TBB 44. We should try them out in my RS while being on Goodwood, see if they function the same. I'll bring a TBB 3, my old 26

Regards,
Cees