[Kemuli]

Alright, got a new one for all of you. Background info, 1992 GTO MR Rhd, bad ecu and attempted to replace with a usdm replica with same part number. No dice. Now I’ve bought a jester chrome ecu, version 3, with tactrix openport 2.0 and cable. All programs function as they should on other cars and the openport works fine on other cars as well.

the issue
After installing the ecu and routing the black and red wires to the back of my obd1 port, red wire to pin 2 and black wire to pin 6. I plug the obd1 to obd2 adapter into it and when I check pin 2 and 16 on the obd2 I get 12 volts. So why is it that when I plug the openport into it it doesn’t light up and fails when you attempt to load a flash into the ecu and evoscan says less than 5 volts detected? I’ve been unable to find any type of solution even after contacting tactrix and chrome. Has anyone encountered an issue like this before? I’ve checked the fuses and everything is good. All connections are secure. All plugs to the ecu are solid.

 

[box]

Check for a good earth at pins 4 & 5 of the 16 pin plug.

 

[Kemuli]

I’m gonna sound very dumb asking this but how exactly would I test? When I put my probe into either 4 or 5 and then to 16 I get negative voltage.(I’m exceptionally bad at anything involving electricity)

 

[box]

Backprobe the connector with some paperclips wound around the probes of the multimeter, if you put your probes in the front you'll spread the terminals and they won't connect properly.

Put the black lead into the "COM" port of the multimeter, put the red one into the VΩ mA port
Put your black multimeter probe into pin 4, put the red one in pin 16, it should read battery voltage (11-12.6v) with the ignition switched on
Put your black multimeter probe into pin 5, put the red one in pin 16, it should read battery voltage with the ignition switched on

If it's reading negative voltage, it's wired incorrectly.

Plug in your openport 2.0 and re-test it as above, you should get the same results.

 

[Kemuli]

Ah okay thank you for the explanation, i am getting negative when I’m testing the grounds so my ground must be wired wrong. Tho I’m not sure how that’s possible is I’ve never touched it, nor would I know where to start to check

 

[box]

What do you mean when you're testing the grounds? When you do what I said in my last post, what does the meter say?

 

[Kemuli]

So pin 4 and 5 on the obd2 adapter are grounds and when I test either of them with pin 16 I get -12.75 volts to my meter. From what it sounds like that’s an indication of a bad ground.

 

[Kemuli]

So I took my battery out and charged it fully I’ve the night and came back to test the probes again, black on 4 and red on 16 gets me nothing and so does 5 and 16. 1 with red and 16 with black gets me 12.75 v and if I swap the red and back I get -12.75

 

[box]

What do you get if you put your black lead on the chassis (a nice shiny bolt stuck to the pillar or something like that) and the red lead in 16?

You'll need to go back to the 12 pin plug and check the ground on that (pin 12). You also need to figure out where the 16 pin plug is getting its 12v supply from.

 

[Kemuli]

Black on chassis and red in 16 didn’t give me anything. Black on chassis and red in 1 gets me 12.75v.

 

[niteninja11]

what voltage do you get on pin 2 to ground? The 2 wires you installed one is a power from the ECU that I noticed never works. This is what your tantrix reads voltage from. I run don’t install mine into the pin and anymore and loop it straight into a empty fuse spot in the fuse panel right there