Teddy952

Almost finished buttoning up the wiring for my TEC3. The good news is that the engine is running and drivable. I'm in the process of tuning now (huge learning curve). The bad news is that I can't seem to get the TEC to control the fuel pump and tachometer. From the posts that I have read the tachometer signal out of the TEC connects to term#2 (black and green wire) on the T1 DME connection in passenger foot well. Term2 on this plug is connected to the TEC's tach output but tach does not move. I connected the oil level sensor wire to this same plug, term8, and that is working fine.

The fuel pump ground wire out from the TEC is connected to term 85b on the DME relay VIA the #5 connection in the T21 plug near brake booster. This is the same manner that the stock ECU grounds the 2nd DME relay to power the fuel pump. I also posted this configuration in the Elecromotive forums and an admin replied stating that how I have it should work. The only way I can get the fuel pump to power on is by hard wiring the #5 connection on the T21 plug to chassis ground. The problem with this is that the pump is always on when the key is in 2nd position.


Continuity is there between the 85b plug on fuse panel and term #5 on the T21 plug. I did check term #5 and it shows +12v only when key is on. Not sure if this is correct. I never touched this portion of the wiring so I'm a bit confused. I tried swapping DME relays as well as checking all fuses.

The fuel pump output wire from the TEC shows +12v 100% of the time, even with unit on/off. I'm waiting to hear back from Electromotive on this...

Thanks!

fortysixandtwo

Its been a few years, but I recall the car side of the tach harness is the green wire in the red, four wire, connector in the passengers side foot well. This is on an 86, if that makes a difference.
I ran a separate relay for my pump, and have it located with the TEC3.

Have you verified continuity from the electomotive, when there is a call for the fuel pump to run?

reno808

Make sure the RPM Tach signal comes from the little 4 wire connector. that connector is by the glove box in the rear.

Did your Tec 3 wire harness come with a plug to connect to the female connection by the brake booster? Make sure the settings on the Tec 3 are correct. I know for the Link if i am not mistaken you can even change the polarity or something like that for something things.

Teddy952

46&2 -- Mine is an 89', I should of mentioned that, the 4 pin connector is the earlier years. Mine has the 8 pin, black flat plug in passenger foot well. Continuity from the TEC plug to the end of lt. green wire used for grounding fuel pump exists. The fuel pump should run for 8 seconds, or whatever time I specify in the software, when key is on. Funny thing is that the fuel pump grounding wire from the TEC always shows +12v.

Reno -- I used a male plug from the old harness and soldered that to the TEC fuel pump wire. The Wintec software that manages the TEC doesn't have that many settings for managing the tach. That being said I tried all of them and still got nothing on the tach.

Thanks

reno808

are you getting the tach signal from that flat plug?

Teddy952

The output for the tach signal is generated by the TEC.

The stock DME tach output signal is sent from term 21 on the DME connector. There are 2 wires coming from term 21. One goes to term 2 on the flat plug and the other goes to term 9 on the KLR plug. Term 2 then connects to the tach in the dashboard.

So Im giving the tach signal from the TEC to the tach via term 2 on flat plug.