Eric_k

Pin 21 "Activation of ABS MIL (ground)" does not light when ABS is activating, it is the warning light. I have 21 connected to Pin 29 on the 968 side. It only lights when there is a problem with the ABS - like if you have an ABS reset switch. It will light when power is killed to the unit.

I did my wiring similar to yours except:
Pin 10 " D+" went to 968 ABS Pin 15 "D +"
I used the 968 ABS computer power to power the control module
Pin 15 "Control module power supply" to 968 ABS Pin 1
Pin 16 "Ground" to 968 ABS Pin 10
For Pins 17,18,19 I used the power/ground wires at the 968 pump.

car_slave

Thanks Eric! I'll give your updates a shot. The pin 1 power (at 968 box) seems to be coming from the same relay as the black and blue wire at the 968 pump end which I connected to new pump 15 power supply. How did you figure out Pin 10 to 968 ABS Pin 15? I'm not sure I understand that one.

Updated list #3: Updated to V 4 - see post below
1. RR sensor ground connect to pin 26+
2. RR sensor signal connect to pin 24
3. —
4. RF sensor ground connect to pin 21+
5. RF sensor signal connect to pin 11
6. LF sensor ground connect to pin 6
7. LF sensor signal connect to pin 4+
8. LR sensor ground connect to pin 9+
9. LR sensor signal connect to pin 8
10. used to detect when vehicle is running (alternator in use) connect to Pin 15
11. K wire ( to OBD connector pin 7 )
12. -
13. —
14. Stoplight switch — connect to pin 25
15. Power to unit - connect to black and blue wire on 944 harness at pump
16. Ground ABS return flow pump - connect to pump mont ground point
17. Positive battery voltage - connect to big red wire on 944 harness at pump
18. Positive battery voltage -- connect to big red wire on 944 harness at pump
19. Ground ABS control module - connect to pump mont ground point
20. Traction control indication light — not used
21. ABS light activation (Ground) — pin 29 (ABS malfunction warning light)
22. -
23. LR speed sensor - connect to pin 17 on 968 speedo
24. RR speed sensor — could also be used as speedo signal

Eric_k

The short answer is because they are both labeled "D+" on the wiring diagrams. The ABS uses it to know the engine is running.
See here: https://rennlist.com/forums/924-931-...out-there.html
I'm not sure why you labeled it "Instrument cluster processor".

car_slave

Thanks agin - that info came from some non-Porsche wiring information for the Bosch 5.3 ABS unit.

rlets

ABS!! It works!!

Thanks for all this information here, Guys. Never could've done it without it. What I found was that the 4-pin connector shown in the diagrams at the link Eric posted is the same on my '87 non-ABS car. That connector has everything I needed:

1 - brake light switch
2 - alternator trigger
3 - ignition switched power
4 - ANTI-LOCK light activation

Just now I started down my steep, wet, cold hill with the bias would all the way rearwards, stomped on the brakes and the car stopped. I could feel the pump pulsing in the pedal and heard a groan that was more subtle than I was expecting. But the car stopped quickly with no lockup.

Awesome!! Maybe now I won't turn so many tires square at the track.

Rich

docwyte

Is the wiring the same on a factory ABS equipped car like my 89 951?

car_slave

Yes, the wiring is the same except that you won't have the 968 speedo to connect. This should also work on a 928 which uses the same ABS pump as the 944. Maybe others too...

Duke

Good work! Looking forward to trying my ABS setup at the track.

Lemming

Now that the 10 pin is connected, hopefully my system will work. I'll find out in three weeks.

I did not attached 10 to the alternator wire, my 10 is on a fused switch that I will turn on after the car starts. I can then use the switch to cycle the abs is the abs light comes on showing a fault. Anyone see any issues with this setup?

car_slave

I'm not sure if the at will actually cycle the unit. I think you'd need to switch power on the wire at pin 15.

Lemming

I have all the abs power running off the same switch.

docwyte

Does the boxster pump have an integral ABS controller or are you guys reusing the 944 ABS controller?

theedge

It is integral.

docwyte

That's what I thought, thanks!

dizzyj

can someone give the cliff notes?
Originally people used the 944 pump with the boxter controller right? but now you use the boxter pump?