Need help from Wiring Guru - TEMS system. Hardwiring HKS TEMS controller

May 18, 2007
704
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Aarhus
I recently bought a HKS Tems controller and since my car is EURO spec and didn't come with TEMS I have wired it in myself a few years ago. And it works fine.

But since I did that I don't have the O1 plug / connector where the HKS TEMS controller plugs in so I have to hardwire it in mostly at the TEMS ECU.

I have identified all the wires but one that goes to the HKS TEMS controller by using the TEWD on cygnus.

The only wire I can't find is the pin 9 on the O1 connector. It does not appear in any of the diagrams on the TEWD. So I don't know what it does.

It is a wire that the HKS TEMS controller intercepts, modifies and passes on (in contrast to tapping into).

So does anyone know which two things pin 9 on the O1 connector connects? If it is any help the color on the HKS patch harness is black on the male part and black/white on the female part.
 
May 18, 2007
704
0
16
52
Aarhus
May 18, 2007
704
0
16
52
Aarhus
All the intercepted signals are switch on/off by the AUTO/MANUAL button.

So it seems that the O1 pin 9 must go to the TEMS ECU. So if anyone has time to measure which pin it goes to on the TEMS ECU I'll be very grateful.
 
May 18, 2007
704
0
16
52
Aarhus
Actually looking at the wiring diagram it seems nothing goes on pin 2, 11 and 20 on the O1 connector. They are not connected on the TEWD. So I was wondering if the missing pin 9 is actually what is denoted at pin 2 on the TEMS diagram and that there is an error in the TEWD regarding the L1 going through pin 2 on the O1 and instead goes through pin 9.

It is a black wire that goes to between L1 on the ECU and H11 on the TEMS ECU.

So if someone could see if the is continuity bewteen the L1 and pin 9 or pin 9 and pin H12?
 
May 18, 2007
704
0
16
52
Aarhus
I think I have solved it. I have a 1992 supplement to the TEWD for the EU model (or so I thought). But it turns out that it is a supplement for all including TEMS cars.

And there I found this:

TEMS3.jpg

Here the O1 plug is called IM1 and you can see that now the O1 pin 2 has been changed to IM1 pin 9. The IM1 and O1 plugs are identical.

So it seems the pin 2 was an error in the TEWD.
 

Drake69

Enjoyin' mah ride...
Aug 24, 2009
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Richmond, Virginia, United States
Good job! I didn't know TEMS wasn't an option on European Supras, that's excellent info.

As far as wiring TEMS direct on a non-TEMS car, you've definitely exceeded my skill on that. I never did find any direct wiring diagrams for the HKS unit beyond what we already had from the instructions, so if you can get this up and working in your car as designed, then you can gather your thoughts together and add a new chapter to the TEMS/HKS book. It would be MUCH appreciated!
 
May 18, 2007
704
0
16
52
Aarhus
I have the final wiring diagram here:

View attachment 68722

In addition the short black/white wire with a spade goes to 12V and the black wire with the ring terminal goes to ground.
 

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